exothermic reaction

In short, I would say that both are correct.

"energy of reactant>energy of product": It should be the potential energy is better.

You can think in this way: using two strong magnets as an example. N pole as +ve charge, S pole as -ve charge, to simulate the bond between two different atoms.

a. Place two magnets about 1 cm apart insert a book with 1 cm think between them. Then feel the strengh you need to separate them.

b. Place two magnets in contact and feel the strengh you need to separate them.

You would find that case b need a stronger strengh and case b is "more stable", so the bond of the product is stronger.

when the magnets are in case a, they have a higher potential energy and there is a tendency for them to move toward each other to release the energy as KE and sound energy. By conservation of energy, energy of the reactant is > energy of product.