Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Ex Input:
The climate is defined as the temperature plus precipitation of an area over a long period of time.

Ex Output:
What is defined as the temperature plus precipitation of an area over a long period of time?


Ex Input:
Unlike ammonia, oxygen cannot be liquefied at room temperature because its critical temperature is below room temperature.

Ex Output:
Unlike ammonia, oxygen cannot be liquefied at room temperature because its what is below room temperature?


Ex Input:
The main functions of epithelia are protection from the environment, coverage, secretion and excretion, absorption, and filtration.

Ex Output:

The main functions of epithelia are protection from the environment, coverage, secretion and excretion, absorption, and this?