星期天，明明同妈妈一起到商店买碗．妈妈挑选碗时，总是将两只碗轻轻碰一碰，听听发出的声音．明明知道妈妈在判断碗的好坏．你知道明明妈妈判断的主要依据是声音的  [ ]

A．音调          

B．响度        

C．音色        

D．音量

After the earthquake, many people had to be _____ in the tents because most of their houses were badly damaged. 

A．put away

B．put out

C．put up

D．put off