The water collected in a reservoir comes from the? A. Rain
B. Stream and river
C. Rain, stream and river
D. Rain, stream, river and sea​

River

Explanation:

The Answer is river because reservoirs are built principally to provide water supply to homes, industry, agriculture as winter storage for crop irrigation or, in some cases, for electrical power generation.

if you mean hydrogen and oxygen then water is the product

answer:

the reaction is type of combination reaction.

explanation:

on the product side, there are 2 molecules of bonded to fe   which means one atom of fe are combined two molecules of . so, balanced chemical equation becomes :

this reaction follows the reaction type of combination reaction. a combination reaction is defined as chemical reaction in which reactants combines together to form a single product.