Question

It is the home of a variety of people, animals, and plants that __7___ to live under very hot and dry conditions.

• A. has learnt
• B. have learnt
• C. had learnt
• D. have been learning

Answer 1

The correct option is B have learnt

Here, 'have learnt' in present perfect tense is correct because it is used indicate an action which started in the past and has continued up untill now. Here, variety of people, animals, and plants that 'have learnt' (present perfect) to live under very hot and dry conditions.
'Has learnt' is incorrect because the subject is in plural, not singular. So, verb has to be in plural (have), not singular (has).
'Had learnt' in past perfect is incorrect because it is used to indicate a completed action of the past that happened before another event took place.
'Have been learning' in present perfect continuous tense is incorrect because it is used to indicate an action that started at some point in the past and may or may not be complete.