Question

a single - celled organism is represented in the diagram shown below. an activity is shown: which substance is the main energy source needed to perform this process? a photosynthesis b atp c enzyme d dna

Explanation:

ATP (adenosine - triphosphate) is the main energy - carrying molecule in cells. It provides the energy for various cellular processes, including those in single - celled organisms. Photosynthesis is a process, not an energy source. Enzymes are biological catalysts and DNA stores genetic information.

Answer:

B. ATP