Molecule having an incomplete octet in the central atom is

Which of the following molecules has one lone pair of electrons on the central atom

In one among the following molecules the state of hybridisation of the central atom is not the same as the others

What would be the shape of XY_(3) molecule if there is no lone pair on the central atom?

In the following questions, a statement of assertion (A) is followed by a statement of reason (R ) A : BeCl_(2) in vapour phase is electron deficient molecule. R : Any molecule in which central atom is having incomplete octet is known as electron deficient molecule.