Prep07 介词先行词问题

毛哥二战要上720

Less than 35 years after the releaseof African honeybees outside Sao Paulo, Brazil, their

descendants, popularly known askiller bees, had migrated as far north as southern Texas.

(A) Less than 35 years after therelease of African honeybees outside Sao Paulo, Brazil,

(B) In less than 35 years sincereleasing African honeybees outside Sao Paulo, Brazil,

(C) In less than the 35 years sinceAfrican honeybees had been released outside Sao Paulo,

Brazil,

(D) It took less than 35 years fromthe release of African honeybees outside Sao Paulo, Brazil,

when

(E) It took less than the 35 yearsafter the time that African honeybees were released outside

Sao Paulo, Brazil, and then

答案是A

我记得介词的先行词不能是介词短语里的词啊，如果是这样，their就没有指代了啊

毛哥二战要上720

DDDDDDDD求大神啊