（）是指以米、画为生要原料，配以适当辅料，在蚀立的生产场所由画点师生产制作的产品。

By the time the new pupil ___ enough courage to raise his hand, the bell__ for the end of the lesson

A．had gathered…was already ringing

B．was gathering…had already rung

C．gathered… had already rung

D．would gather… have rung