With 和 After 的文意判斷 - 英檢

____ collecting health data from thousands of nurses,Michels and
colleagues reported in 1997 that women had weighed about 5.5 pounds at birth
had half the risk of breast cancer in women aged 50 or younger.

(A) after
(B) with



疑問：為甚麼是A而不是B

我同意選A無誤

但不是B的理由是？

多謝幫忙！

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