23. Assertion : Heavy water is used as moderator in nuclear reactor. Reason : Water cool down the fast neutron.

(a)       If both assertion and reason are true and the reason is the correct explanation of the assertion.

(b)       If both assertion and reason are true but reason is not the correct explanation of the assertion.

(c)        If assertion is true but reason is false.

(d)       If the assertion and reason both are false.

(e)       If assertion is false but reason is true.

Answer:  C

(4)