Assertion (A): Energy is required to carry out different life processes.
Reason (R): Energy is obtained in the form of ATP in the mitochondria.

Select the correct option:

(a) Both A and R are true, and R is the correct explanation of A.
(b) Both A and R are true, but R is not the correct explanation of A.
(c) A is true, but R is false.
(d) A is false, but R is true.