Q1. Nobody ----- that he is innocent.
A. is believing
B. .believes
C. believe
D. believed
Answer - Option B
Explanation - Since the verb in the subordinate clause is in the present tense, the verb in the main clause is also likely to be in the present or future tense. A past tense seems improbable. Nobody is singular and hence the verb takes the marker -s.
Q2. Mother ------ busy cooking for the guests who are arriving in the evening.
A.was
B. .has been
C. has
D. had been
Answer - Option B
Explanation -To talk about a situation that started in the past and has continued up to the present, we use the present perfect tense.