It is so wet there that the trees are extremely tall some over 90 metres.A. are measured

问题补充：

It is so wet there that the trees are extremely tall, some over 90 metres.

A. are measured

B. measuring

C. measured

D. measure

答案：

A. are measured

(答案→)B. measuring

C. measured

D. measure

解析：考查独立主格结构，句意：这儿是如此潮湿，以至于树很高，一些高达90米。the trees are extremely tall是完整的句子，中间没有连词，说明后面是独立主格结构， some是逻辑主语，后面是非谓语动词做状语，measure后面接数词，表示：长，宽，高是多少的时候，measure是不及物动词，用现在分词。选B。