A periodic table is showing the element Sodium as below. What is atomic number and mass number of the element sodium?

(A) Atomic Number = 11 and Mass Number = 23
(B) Atomic Number = 23 and Mass Number = 11
(C) Atomic Number = 11 and Electronegativity = 23
(D) Atomic Number = 11 and Valency = 23

The answer is: (A) Atomic Number = 11 and Mass Number = 23