S.H.O. stands for

The abbreviation for S.H.O. is Station House Officer.

A police station's Station House Officer is in charge.

In other words, the SHO is the commandant of the police station.

The filing of complaints is the responsibility of the SHO.

Complaints are usually filed as a Formal Investigation Report (FIR).

Hence, the correct option is A,

S.H.O. stands for Station House Officer