Please correct my answer

1.My boss told me ________ the meeting.
(A) don't forget
(B) not to forget
(C) not forgetting
(D) didn't forget

ans (B) not to forget

2.A: Should people on sick leave be allowed to accumulate vacation time?
B: ______ federal regulations dictate our company leave policy.
(A) Lacking options,
(B) We are limited because
(C) It's a moot point that
(D) Due to the fact that

ans (B) We are limited because

3.A: When will we start legal action on this default?
B: Filing a lawsuit _______.
(A) will be my priority tomorrow morning
(B) in the filing cabinet is my priority tomorrow morning.
(C) and to begin prosecution are my priorities tomorrow morning
(D) the legal action will start tomorrow morning.

ans (A) will be my priority tomorrow morning

4.A: Were you able to attend the semi-annual managers meeting yesterday afternoon?
B: No, I _______, but I was delayed by a lengthy conference call with an important client.
(A) should have attended
(B) could have being present
(C) must have gone
(D) may have appeared

ans (A) should have attended