Q28:

Some scientists contend that many species of dinosaur had a metabolism more like a warm-blooded mammal’s than a cold-blooded reptile’s.

1. that many species of dinosaur had a metabolism more like
2. that the metabolism of many dinosaur species were more like
3. that the metabolisms of many species of dinosaurs were more like those of
4. there were many species of dinosaurs that had metabolisms more like those of
5. there were many dinosaur species that had a metabolism more like that of

弱弱的再问：A错在哪？比较的主题是metabolism，它那里也很明确啊

而且B中metabolism是不可数名词，更不可能接were吧？

my two cents:

A is wrong, 比较对像不具可比性. species VS. a warm-blooded mammal's.

I do agree with you. in B, "was" should be used instead of "were" because "metabolism" is singular. it might be a typo?

However, although B has a problem in Grammar, others are worse than B. Thus, B is still the best.