A．The weekend has decreased in length.

B．The number of national holidays has increased.

C．People work fewer days per week.

D．People work more hours each day.

拌合楼按工艺流程分层布置，分为进料、贮料、配料、拌合及出料共五层，其中（）是全楼的控制中心，设有主操纵台。

A.进料层 

B.配料层 

C.贮料层 

D.拌合层