IN: Which person is they?
The police arrested the criminals since they enforce the law.
OUT: The police

IN: Which person is he?
It annoyed Chris when Sebastian jangled his keys because he wanted to make fun.
OUT: Sebastian

IN: Which person is he?
The advisor told the President that he was resigning.
OUT: The advisor

IN: Which person is he?
Student A beat student B, because he studied.
OUT:
Student A