What does Jack steal from the other group of boys? Why?

The conch. To have power over everyone.
The pig’s head on a stick. To scare the beast.
Piggy’s glasses. To start their own fire.
Fruit. To have something to eat.

Piggy's glasses. To start their own fire.

Jack steals Piggy's glasses from the other group of boys. He does this in order to start their own fire.