Assertion (A): x³ + x has only one real zero.
Reason (R): A polynomial of nth degree must have n real zeroes

a. Both (A) and (R) are correct, and (R) is the correct explanation of the (A)
b. Both (A) and (R) are correct but (R) is NOT the correct explanation of the (A)
c. (A) is correct but (R) is incorrect
d. (A) is incorrect but (R) is correct