Assertion (A): Only the relevant costs should be taken into consideration for decision-making.
Reason (R): All variable costs are relevant costs, and all fixed costs are irrelevant costs.

A. Both (A) and (R) are correct

B. (A) is correct, but (R) is incorrect

C. (R) is correct, but (A) is incorrect

D. Both (A) and (R) are incorrect

Answer: Option B