条件句省略和非谓语动词的疑问

.The government managed to have two chemical factories built,though________by the citizen.

答案是opposed to ,为何不选having been opposed to 呢，我查到网上也有though having been done 的使用方法

The government managed to have two chemical factories built, though opposed by the citizens.

过去分词的一般体，本身就能表示“完成”，没必要用完成体。假如用完成体，则不能用连词 though。连词后的省略，是去掉“主语 + be”，剩下doing 或 done，没有having been done。