“小孩尖叫声刺耳”说明声音的______，李白的诗句“不敢高声语，恐惊天上人”中的高是指______，龙舟赛时，阵阵鼓声是由于鼓面______而产生，并经过______传入人耳．

---- Oh, it’s raining hard outside. Do you think the milkman will arrive?

---- Of course. He will come on time ________ it rains.

A．in case

B．as long as

C．ever since

D．even though