Welcome to the Science Museum, everyone! This stone axe _______ in South Africa and

experts can’t be exactly sure about its use.

A．had been found

B．was found

C．has been found

D．would be found

—Do you know when World Non-smoking Day is?

—___________.[ ]

A. It's a fine day

B. It's May 31

C. It's Sunday

D. It's time to give up smoking