同位语的问题！求解

xiaobaibai92112

The World Wildlife Fund has declared that global warming, a phenomenon most scientists agree to be caused bv human beings in burning fossil fuels, will create havoc among migratory birds by altering the environment in ways harmful to their habitats.
(A) a phenomenon most scientists agree to be caused by human beings in burning fossil fuels,
(B) a phenomenon most scientists agree that is caused by fossil fuels burned by human beings,
(C) a phenomenon that most scientists agree is caused by human beings' burning of fossil fuels,
(D) which most scientists agree on as a phenomenon caused by human beings who burn fossil fuels,
(E) which most scientists agree to be a phenomenon caused by fossil fuels burned by human beings,
答案为C，但是C中most scientists agree is， 俩动词连用？这样可以吗？还是有什么特殊结构？
求大神解释

ayoyoyo

most scientists agree是插入语，跟同位语无关。

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