The squirrels buried the nuts so they would not get lost.

Who is "they" in this prior sentence?
the nuts
Parents send their children to bed, and they have to listen to authority since they are dependents.

Who is "they" in this prior sentence?
their children
The US Health inspection board shut down several food factories, but they discovered that many rules and regulations were violated.

Who is "they" in this prior sentence?

The US Health inspection board