15. On the way, you can see this sign and it says:

A. The trucks aren’t allowed to move into this way.

B. The trucks must turn on lights when moving.

C. The black trucks must be allowed to move.

D. The black trucks can’t move when lights are working.

16. What does this sign say?

A. You must check the elevator.                               

B. You are not allowed to use the elevator.

C. You can use the elevator.

D. Only adults can use the elevator.