In a face centered cubic lattice atoms A are at the corner points and atoms B at the face centered points .If atom is missing from one of the face centered points, the formula of the ionic compound is :

Question

$(a)\;AB_{2}\qquad(b)\;A_{5}B_{2} \qquad(c)\;A_{2}B_{3}\qquad(d)\;A_{2}B_{5}$