Answer:
C. Reduction is a correct answer.
Step-by-step explanation:
Reduction is the process in which substance gain electrons.
The reactant is become reduced and has a negative charge, once it gains electrons.
In the reduction process, oxidation number get decrease by gaining the electrons.
Example of reduction
In photosynthesis process transfer of electron is an example of an oxidation-reduction reaction.
water gets oxidized by losing the electron and carbon dioxide gets reduced by gaining the electrons.
Thus Reduction is the term for a reaction in which a substance gains electrons. so the correct answer is (c).