A. The new staff will be given all the help by him
B. The new staff will have been given all the help by them
C. The new staff will be given all the help by them
D. The new staff will be given all the help by us
Explanation
Option A is the correct answer because have been was mentioned in second option which is used for perfect tense, the word him was mentioned in third option which is used for he not they, the word us was mentioned in fourth option which is used for we not they.