Answer:
A. Collection
Explanation: A resevoir is an artifical lake where water is stored and is therefore a collection of water.
I don't have an answer for you, but I do have an important hint ... one that will
stand you in good stead as you go further in your mathematical studies:
The reason there's a drawing right next to this question in the book or on the
homework sheet is that the question can't be answered without the drawing.
Weather is known over short periods of time and can be inaccurate, climate is figured out over long periods of time and effects a larger area