Çözüldü Sentence Completion - Grammar - Time Consistency with Active and Passive Voice

Hundreds of cans of tuna ______ the factory because some of them ______.

A) to be recalled by / had been found contaminating
B) would recall / have been contaminating
C) were recalled by / were found to be contaminated
D) had to be recalled by / will have been contaminated
E) will be recalling / are to contaminate

Correct Choice: C (Past Passive Voice)

Adapted from "Barron's TOEFL", 1988, page 133