Assertion (a) The Aravalli ranges have become worn down due to the effect of denudation. Reason (b) The Aravallis are the oldest folded ranges of the world. Which of the following conclusions are correct in the context of the above statements.

• A. (a) and (b) are both correct and (b) is the correct explanation of (a).
• B. (a) and (b) both are correct but (b) is not the correct explanation of (a).
• C. (A) is correct while (B) is incorrect.
• D. (A) is wrong while (B) is correct.