The right answer is C)Energy stored as ATP
Cells have different morphologies, structures, and roles, but their basic operation is the same. One of the main activities of the cell is its survival.
ATP is precisely a molecule essential to the life of the cell.
The degradation reactions are called exoenergetic because they release energy and the synthesis reactions are called endoenergetic because they consume: the energy of the first reactions allows the realization of synthesis reactions.
This is only possible if an intermediary is able to store this energy and restore it as needed: the ATP molecules play this role of intermediary.