囧哥做语法36

囧囧哥UID：3408678

The survival of coral colonies, which are composed of innumerable tiny polyps living in a symbiotic relationship with brilliantly colored algae, are being threatened, experts say, not only by pollutants like agricultural runoff, oil slicks ,and trash, but also by dropped anchors, probing divers, and global warming.
A are being threatened, experts say, not only by pollutants like
B are being threatened, experts say,by not only pollutants such as
C is not only being threatened, experts say, by pollutants such as
D is not only being threatened, experts say, by pollutants like
E is being threatened, experts say, not only by pollutants such as

句子结构：
The survival of coral colonies, which 从句，are being threatened...
主语是the survival所以谓语用单数，排除AB
根据not only...but also 的平行结构，发现CD不平行，选择E