Regarding Classes Chondrichthyes & Osteichthyes of Pisces: Assertion (A): They are called cold-blooded animals. Reason (R): They are aquatic (marine or fresh water) and as they in continous contact with water their blood is cold. Regarding (A) and (R) :

Question

( a ) A is incorrect but R is correct
( b ) Both A and R are correct but R is not the correct explanation for A
( c ) A is correct but R is incorrect
( d ) Both A and R are correct & R is the correct explanation for A