TASK DEFINITION: In this task, you are given a sentence and a question, you would be asked to create the answer which is contained in the sentence provided.
PROBLEM: Sentence: Deep currents are caused by differences in density at the top and bottom of the ocean. Question: What is caused by differences in density at the top and bottom of the ocean?

SOLUTION: deep currents

PROBLEM: Sentence: The epidermis of a leaf contains openings known as stomata, through which the exchange of gases takes place. Question: Which part of a leaf contains openings known as stomata, through which the exchange of gases takes place?

SOLUTION: epidermis

PROBLEM: Sentence: Echinoderms possess a water-based circulatory system. Question: What kind of system do echinoderms possess?

SOLUTION:
water-based circulatory