The shape of which of the following can be satisfactorily explained by the directional overlap concept of V.B.T.?

It is because in C, N and O, all the three 2p-orbitals at 90o to one another and none of the given cases have H—A—H angle 90o. In NH3, it is 107o; in H2O, it is 104.5o and CH4, it is 109o28'.