Question

Carnivorous mammals can endure what would otherwise be lethal levels of body heat because they have a heat-exchange network which kept the brain from getting too hot.

• A. which kept
• B. that keeps
• C. which has kept
• D. that has been keeping
• E. having kept

Answer 1

The correct option is B that keeps

The given sentence gives a fact about why carnivorous mammals can endure a lot of body heat. In such cases, we always use present tense form of the verb i.e 'keeps' in given context. Therefor, options A, C, D and E are incorrect.

Whenever the second clause in a sentence(brain from getting too hot) is important to the first clause(mammals can endure lethal levels of body heat), we use 'that'. 'Which' is used when the reader can ignore or omit the second clause in the sentence as it is not of any importance.

Therefore, option B is the correct answer.