I would say that would be DNA
Hope this helps :)
Basically, the P-P chain turns 4 protons into: 1 neutrino, 1 gamma ray, 1 positron, 1 helium nucleus.
A gamma ray = energy.
The chain converts hydrogen into helium and makes energy.
This is all occurring through fusion reactions where 2 protons basically smash into each other. But, it could also be e.g. a proton smashing with a deuterium nucleus. Or, other nuclei smashing together to make something else.
Hope this helps!
I don’t really understand the question but i’m assuming that’s there’s a chemical reaction happening when the bicyclist is eating the food to get energy to bike?
It so should be A.
Mark branliest if it is correct!