water is essential to life (an ,the , a,)​

Leave empty

Explanation:

Water is uncountable, so definitely not "a" or "an".

We're left with either leaving it empty or "the". But "the" suggests that it's not just any water, but some type/body of water in particular, which is not the case.

Water is essential to life.

explanation:

you only need simple sentences to answer this. just answer these questions.

what do you think annie thinks of the mother? do you think annie believes the mother is a fit mother for helen.

what about the father? what would annie think of him? she might not like him, but does she respect him.

how about the son? would annie think he is the only voice of sanity in an insane place?

what about helen herself? this is the key question. how does she see helen? what do you suppose she thought her first job was going to be.

these aren't hard questions. just state the obvious. annie is not that well educated: she just knows what she has to do. write it that way.

you can do it if you've read the book or seen the play or movie.