not only but also - 英檢

This incident has not only damaged the public health and hurt
_________________ (A)

consumer confidence, but has also delivered a heavy blow to country's image
______________________ (C)

in terms of food quality and safty.

答案是A

是因為少了to? 如果是的話

想知道有加to跟沒加的差別

我選C 是想說 因為has not only

has 在not only 前面 所以 but has also delieverd 不需要再加has

還是也可以加?

謝謝解答^^

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