Question

Assertion: Nelson Mandela, being tried for treason by the white South African government.
Reason: Apartheid was the name of a system of racial discrimination unique to South Africa.​

Answer 1

Both A and R are true but R is not the correct explanation of A

Answer 2

Option B) Both A) and R) are true but (R) is not the correct explanation of (A). is the correct answer.

Because

The Treason Trial was a trial in Johannesburg in which 156 people, including Nelson Mandela, were arrested in a raid and accused of treason in South Africa.

And  Apartheid was a system of institutionalized racial segregation that existed in South Africa and SouthWest Africa.

So, both are different sentences.

Therefore, Both A) and R) are true but (R) is not the correct explanation of (A).