Assertion (A): In bcc, the available volume is more efficiently used than in simple cubic packing.
Reason (R): In simple cubic arrangement, the number of spheres belongs to a unit cell is equal to one whereas in bcc, it is equal to 2.
(a) Both A and R are correct and R is the correct explanation of A
(b) Both A and R are correct R is not the correct explanation of A
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
