Question

What is a characteristic of all fuel cells?

Energy from the Sun is converted into electricity.
Electrical energy is produced from oxidation reactions.
Oxidation reactions are used to produce thermal energy.
A constant source of energy is not required.

Answer 1

B. Electrical energy is produced from oxidation reactions.
I don't have an explanation for this though. Do you need one? I can probably look it up.

Answer 2

Electrical energy is produced from oxidation reactions.

Step-by-step explanation:

In fuel cells elecric energy is produced from the oxidation of reactants, that fuel is often Hydrogen, that is storaged in the fuel cell and then it just grabs oxygen from the air and converts that chemical reaction of oxidation in electric current.