The news came _______the British Queen’s Mother celebrated her 101st birthday in good health, _____ isn’t surprising，because she lives an easy life and gets the best medical care.

A．that/which

B．which/which

C．that/that

D．when/as

双工制通信就是指移动通信双方可（）进行发信和收信，这时收信与发信必须采用不同的工作频率，称为频分双工。