------You must hand in your report before September 10, which is the______?

------Ok. I will try my best to meet it. Thank you.

      A. need                      B. deadline                     C. regulation               D. agreement

--You must hand in your report before September 10, which is the______?

--Ok. I will try my best to meet it. Thank you.

A．need            B．deadline          C．regulation          D．agreement