— It is better for you to lose weight by taking exercise every morning.  

—  I think your suggestion deserves ______. [ ]

A. try            

B. tried            

C. to be tried        

D. to try

某工程双代号网络计划如下图所示，其中E工作的最早开始时间和最迟开始时间是（）。

A.3和5

B.4和5

C.3和6

D.4和6