Five people joined the job and seven ______.
Five people joined the job and seven ______.
A: resigned
B: have resigned
C: resign
D: None of these
The second clause describes a present result that affects the current state. Present perfect fits that sense. Have resigned marks an action with present relevance. Simple past would mark a finished past point without linkage. Present simple would be ungrammatical here. Therefore have resigned is the correct tense for balance and meaning.