The argument depends on the assumption that

A.     at least some imperfect pastries were baked during the day shift at Acme Bakery last      week

B.      not all of the pastries that the night-shift quality control inspectors judged to be      imperfect were in fact imperfect

C.     the night-shift quality control inspectors received more training in quality control     procedures than did the day-shift quality control inspectors

D.     in a normal week, fewer than six percent of the pastries baked during the night shift at Acme Bakery are found to be imperfect

E.      there are only two shifts per day at Acme Bakery, a day shift and a night shift

정답이 A라고 나와 있는데, b가 아닐까라고 계속 생각이 듭니다. 

day shift에서 imperfect가 안나왔는데 답에선 imperfect가 dayshift에도 나왔다고 하니까, 앞뒤가 안맞는거 아닌가요 ㅠ.

도와주세요!