补全对话(根据对话内容，选择恰当的选项，使对话完整通顺。)

A. Wear the hats and glasses. B. Yes, there are. C. Great! D. They are dangerous.

A: Children, we're going to visit a factory this afternoon.

B:

A: The factory makes crisps.

B: Are there many machines in the factory?

A:

B: Can we touch the machines?

A: No, you can't. Don't touch the machines.

B: What do we wear?

A:

B: OK.