Immediate source of energy for cellular metabolism is:

Explanation

ATP (adenosine triphosphate) is produced through various cellular processes, primarily during cellular respiration and photosynthesis.The three main stages of cellular respiration are glycolysis, the citric acid cycle (Krebs cycle), and oxidative phosphorylation (electron transport chain and chemiosmosis).Photosynthesis is the process by which plants, algae, and some bacteria convert light energy into chemical energy in the form of glucose. It consists of the light-dependent reactions and the light-independent reactions (Calvin cycle).