Is this sentence complex compound or simple? The question is, when water evaporates from the sea it becomes fresh water

Answer 1

It has one independent clause:
it becomes fresh water

and one dependent clause:
when water evaporates from the sea

What kind of sentence is it?

Answer 2

There's a third, isn't there?

Answer 3

Oops. My bad. I misread. Ms. Sue is quite correct.

Answer 4

I read a third clause at first, too.