Social differences are mostly based on accident of birth. But some of the differences are based on our choice too.
(a) (i) The social differences are mostly based on accident of birth.
(ii) We belong to a community because we were born into it
(iii) We all experience social differences based on accident of birth in our everyday life
(iv) People around us are male or female, they are tall and short, have different complexions or have different physical abilities or disabilities. 
(b) (i) Social differences based on our choices.
(ii) For example some people are atheists. They don't believe in God or any religion.
(iii) Some people choose to follow a religion other than the one in which they were born.
(iv) Most of us choose what to study, which occupation to take up and which games to play or which cultural activities to take part in.
(v) All these lead to formation of social groups that are based on our choices. 

(a) The International Olympic Association held Carlos and Smith guilty of violating the Olympic spirit by making a political statement.
(b) Their medals were taken back.
(c) Back home, they were subjected to a lot of criticism.
(d) Norman too suffered for his action and was not included in the Australian team for the next Olympic.
(e) But their action succeeded in gaining international attention for the Civil Rights Movement in the US.

(a) Social differences divide similar people from one another, but they also unite very different people.
(b) People belonging to different social groups share differences and similarities cutting across the boundaries of their groups.
(c) Carlos and Smith were in one way (both were African-American) and thus different from Norman who was white. But they were also all similar in other ways - they were all athletes who stood against racial discrimination.

(a) In this extract, Rev. Matin Luther King Jr. is talking about racism in USA.
(b) He is referring to the segregation policies adopted by the Whites towards the coloured people. He aspires for a country where there will be security for all; where racial abuse will not occur; and where everyone will be treated as equal irrespective of the colour of their skin.
(c) This speech and the incident at the Mexico Olympics are both part of a movement that wanted to heighlight the plight of the African-American people.

(a) A combination of social divisions and politics can be really dangerous.
(b) A democracy involves competition among various political parties.
(c) As their competition tends to divide society, if they start competing in terms of some existing social divisions, then it can convert those social divisions into political divisions, which can lead to conflict, violence and even disintegration of the country.
(d) Northern Ireland is the site of a violent and bitter ethno-political conflict.
(e) Its population is divided into two major sects of Christianity: 53 percent are Protestants, while 44 per cent are Roman Catholics.
(f) The Catholics were represented by Nationalist parties who demanded that Northern Ireland be unified with the Republic of Ireland, a predominantly Catholic country.
(g) The Protestants were represented by Unionists who wanted to remain with the UK, which is predominantly protestant.
(h) In Northern Ireland, hundreds of civilians, militants and security forces were killed in the fight between Unionists (represented the Protestants) and Nationalists (represented the Catholics) and between the security forces of the UK and the Nationalists.
(i) Political competition along religious and ethnic lines resulted in the disintegration of Yugoslavia into six independent countries.
(j) Social divisions affect voting in most of the countries. People from one community tend to prefer some party more than the others.
(k) Social division does not lead to disintegration of the country if it is respected and dealt with properly.
(l) However, the combination of social divisions and politics is not always negative.
(m) The political expression of social divisions allows marginalised and disadvantaged social groups to express their grievances and ask the government to rectify them.
(n) The system of reservation of seats in Indian legislatures for the socially disadvantaged has allowed such social groups to have an adequate representation in the decision making process.

(a) Northern Ireland is the site of a violent and bitter ethno-political conflict.
(b) Its population is divided into two major sects of Christianity: 53 percent are Protestants, while 44 percent are Roman Catholics.
(c) The Catholics were represented by Nationalist parties who demanded that Northern Ireland be unified with the Republic of Ireland, a predominantly Catholic country.
(d) The Protestants were represented by Unionists who wanted to remain with the UK, which is predominantly protestant.

(a) Social division takes place when some social difference overlaps with other differences. The difference between the Blacks and Whites becomes a social division in the US because the Blacks tend to be poor, homeless and are discriminated.
(b) In our country, Dalits tend tie be poor and landless. They often face discrimination and injustice. Situations of this kind produce social divisions, when one kind of social difference becomes more important than the other and people start feeling that they belong to different communities.
(c) If social differences cross cut one another, it is difficult to differentiate one group of people against the other. It means that, groups that share a common interest on one issue are likely to be in different sides on a different issue
(d) In Northern Ireland, class and religion overlap with each other. If you are Catholic, you are also more likely to be poor, and you may have suffered a history of discrimination.
(e) In the Netherlands, class and religion tend to cut across each other.
(f) Catholics and Protestants are about equally likely to be poor or rich. (g) The result is that Catholics and Protestants have had conflicts in Northern Ireland, while they do not do so in the Netherlands.
(h) Overlapping social differences create possibilities of deep social divisions and tensions. Crosscutting social differences are easier to accommodate. ​​​​​

(a) Social division takes place when some social difference overlaps with other differences. The difference between the Blacks and Whites becomes a social division in the US because the Blacks tend to be poor, homeless and are discriminated.
(b) In our country, Dalits tend tie be poor and landless. They often face discrimination and injustice. Situations of this kind produce social divisions, when one kind of social difference becomes more important than the other and people start feeling that they belong to different communities.
(c) If social differences cross cut one another, it is difficult to differentiate one group of people against the other. It means that, groups that share a common interest on one issue are likely to be in different sides on a different issue
(d) In Northern Ireland, class and religion overlap with each other. If you are Catholic, you are also more likely to be poor, and you may have suffered a history of discrimination.
(e) In the Netherlands, class and religion tend to cut across each other.
(f) Catholics and Protestants are about equally likely to be poor or rich. (g) The result is that Catholics and Protestants have had conflicts in Northern Ireland, while they do not do so in the Netherlands.
(h) Overlapping social differences create possibilities of deep social divisions and tensions. Crosscutting social differences are easier to accommodate. ​​​​​

Differences in overlapping and cross-cutting differences are
Overlapping Social Differences
These differences happen when some social differences overlap other differences. It becomes a social division when some social differences are joined by another set of social differences. For example, the difference in the Blacks and the Whites in America is due to their different race which is a social difference. It becomes a social division when, the income factor is also added in that. The Blacks tend to be poor and homeless, while the Whites tend to be rich and educated. This creates a division in the people, making them feel that they belong to different communities.
In our country, Dalits tend to be poor and landless. They often face discrimination and injustice. Situations of this kind produce social division.
Cross-cutting Social Differences
Cross-cutting differences happen when one type of social difference is weakened by another set of social differences. Then, it becomes difficult for group of people into a single category because they are going to have different opinions and views on different matters.On some matters, their might be agreement on a particular issue, but there might be disagreement on another issue. For example, people in the Netherlands are predominantly Christian, but divided between Catholics and Protestants. Here class and religion cross-cut each other. Catholics and Protestants are about equally likely to be poor or rich and they do not have conflict between them.