Which of the following violate the principles of equality? And why?

(a) Every child in class will read the text of the play by turn.

(b) The government of Canada encouraged white Europeans to migrate to Canada from the end of the Second world War till 1960.

(c) There is a separate railway reservation counter for the senior citizens.

(d) Access to some forest areas is reserved for certain tribal communities.

(a) This does not violate the principles of equality.

Because every child is asked to do the same activity in the class, without any discrimination.

(b) This statement violates the principle of equality.

Because the policy of the Canadian Government is based on colour discrimination.

(c) It is not violating the principle of equaltiy. 
This is very much mentioned in the constitution of India, the affirmative action.

(d)This statement is violating the principle of equality.

All tribal communities sustain their live through forest, so some communities should not survive at the cost of other.