某地1991～1995年床位发展情况如下：

1995年的环比增长速度为（）。

A.A

B.B

C.C

D.D

E.E

A work authorization system can be used to （）．

A．manage who does each activity

B．manage what time and in what sequence work is done

C．manage when each activity is done

D．manage who does each activity and when it is done