— Whats the noise? It sounds as if it comes from upstairs. — _____. It must be the window-cleaner w

— What"s the noise？ It sounds as if it comes from upstairs.

— _____. It must be the window-cleaner working, next door.

[ ]A. I"m not sure

B. I hope not

C. I"d rather not

D. I don"t think so