阅读短文，根据短文内容选择正确的答案。

Big Bull looked at the grass and the trees. He looked at the fence. This was his home. He was bored at home.

Big Bull was not staying here. He pushed down the fence and ran into the city. When people saw him coming, they ran into a shop. Big Bull ran after them. People ran up the escalator (自动扶梯). So did Big Bull. But—oops! Big Bull got stuck.

A man shouted, "Get the fire fighters! They will have to come and help!" The fire fighters came with tools. They pushed the escalator out and they pushed Big Bull off. "Come on!" said the fire fighters. "We will take you home. But don't come back here again!" When Big Bull got home, he looked at the grass and the trees. He was not bored because home was good.