Hard work is vital _______ your success in the future（）

It is vital that the work _______ in time.

A. is done

B. be done

C. are done

D. was done

A．a hard world

B．a vital human need

C．a nice and straightforward life

D．enough money and honourable life

A.IEEE库

B.VITAL库

C.STD库

D.WORK工作库

A.IEE库

B.VITAL库

C.STD库

D.WORK工作库

A.IEEE库

B.VITAL库

C.STD库

D.WORK工作库

A.IEEE 库

B. VITAL 库

C. STD库

D. WORK工作库

A、IEEE

B、WORK

C、VITAL

D、STD

[A] it’s necessary to ensure the accuracy of the experiment

[B] online collaboration is becoming more and more important

[C] the experimenters want to see whether collective intelligence will be showed

[D] the experimenters want to prove social ability is vital to every team

求给出正确答案及解析，谢谢！

A.a hard work, to work hard

B.hard work, to work hard

C.a hard work, work hard

D.hard work, work hard

A.not to work hard

B.work not hard

C.not work hard

D.doesn’t work hard