Which of the following contains the same number of atoms as 12 gms: of Magnesium (Atomic weights : Mg = 24, C = 12, Ca = 40)

A. 10 gms of calcium

B. 20 gms of carbon

C. 20 gms of calcium

D. 12 gms of carbon

Please do not use chat terms. Example: avoid using "grt" instead of "great".