Assertion: Shielding effect increases as we go down the group.
Reason: More is the number of electrons in the penultimate shell, more is shielding.

Options

A. Both (A) and (R) are true and (R) is the correct explanation of (A)
B. Both (A) and (R) are true and (R) is not the correct explanation of (A)
C. (A) is true but (R) is false
D. (A) is false but (R) is true