If A B, then A – B is

Given that A B that means B contains all the elements that A contains.

e.g., A = {9, 8, 4, 6} B = {9, 8, 4, 6, 7, 0, 1}

we can see that B contains all the elements of B

So, A B

Let us consider two sets which is A B

A = {9, 8, 4, 6} B = {9, 8, 4, 6, 7, 0, 1}

A – B means we eliminate all the elements of B from A.

A – B = {9, 8, 4, 6} - {9, 8, 4, 6, 7, 0, 1}

= {} ⇒ null set.

Option D is the correct answer.