What is the formula of calcium phosphide?

A.     \({\text{C}}{{\text{a}}_{\text{2}}}{{\text{(P}}{{\text{O}}_{\text{3}}}{\text{)}}_{\text{3}}}\)

B.     \({\text{C}}{{\text{a}}_{\text{2}}}{{\text{P}}_{\text{3}}}\)

C.     \({\text{C}}{{\text{a}}_{\text{3}}}{{\text{(P}}{{\text{O}}_{\text{4}}}{\text{)}}_{\text{2}}}\)

D.     \({\text{C}}{{\text{a}}_{\text{3}}}{{\text{P}}_{\text{2}}}\)

D