QUES:
Who is they in the following sentence?

The NFL generates obscene amounts of revenue compared to the MLB, because they are not as popular to watch.

ANS:
the MLB

QUES:
Who is they in the following sentence?

The civilians had to flee the encampment from the thugs because they feared for their lives.

ANS:
The civilians

QUES:
Who is it in the following sentence?

The music player did not open the file because it was in the wrong format.

ANS:
the file