Assertion : `4d` and `5d` series elements have nearly same atomic radius.
Reason : Lanthanoid contraction.
A. Statement-1 is true , Statement-2 is true and Statement-2 is correct explanation for Statement-1
B. Statement-1 is true, Statement-2 is True and Statement-2 is Not correct explanation for statement-1
C. Statement-1 is true, Statement-2 is False
D. Statement-1 is False, Statement-2 is True