What role does ATP play in cellular processes?

ATP, or adenosine triphosphate, functions as the primary energy carrier in cells, which is why the answer is correct. It is often referred to as the "energy currency" of the cell because it is used to store and transfer energy for various biochemical reactions. ATP releases energy when it is hydrolyzed (converted to ADP and inorganic phosphate), which is then utilized to fuel cellular processes such as muscle contraction, active transport of molecules across membranes, and metabolism.

By acting as a universal energy donor, ATP ties together various energy-requiring processes within the cell. Without it, many vital functions, including biosynthesis, movement, and signal transduction, would not occur efficiently.

The other options address functions that are more specific or unrelated to ATP. For instance, ATP is not a structural component of cells, nor does it store genetic information, which is carried by DNA. While ATP is involved in protein synthesis through its role in powering the machinery that synthesizes proteins, it is not directly responsible for the process itself. Thus, the primary role of ATP is indeed as an energy carrier, central to cellular metabolism and function.