Read the given statements and conclusions carefully and decide which of the conclusions logically follow(s) from the statements.
Statements:
I. All kings have grey hair.

II. Some knights become kings.
Conclusions:
I. All knights have grey hair.
II. All grey-haired knights are kings. ​​​

I. All kings have grey hair.

II. Some knights become kings.

I. All knights have grey hair - False (According to the given statements, some knights become kings and all kings have grey hairs. So, from this, it can be inferred that some knights may have grey hair. Thus, this conclusion does not follow.)

II. All grey-haired knights are kings - False (All grey-haired knights may not be kings because in the statements it is given that all kings have grey hair, but it is not justified that all grey-haired are kings. Thus, this conclusion does not follow.)

So, neither conclusion I nor II follows.

Thus, the correct answer is (a).