The atomic numbers of the elements Na, Mg, K and Ca are 11, 12, 19 and 20 respectively. The element have the largest atomic radius is

Q. The atomic numbers of the elements Na, Mg, K and Ca are 11, 12, 19 and 20 respectively. The element have the largest atomic radius is:

A.            Mg

B.            Na

C.            K

D.            Ca

Answer: K