—Do you know that our school has been named Green Olympic Demonstration School?

—Yes. We are all excited ___________ that.

A．at

B．for

C．about

D．with

常用电光源中，属于热致发光的电光源是（）。

A.白炽灯

B.卤钨灯

C.金属卤化物灯

D.汞灯