Which carbohydrate is primarily found in plant cells?

Starch is primarily found in plant cells and serves as the main storage form of carbohydrates in plants. It is a polysaccharide composed of numerous glucose units, which plants synthesize through the process of photosynthesis. When plants have excess glucose, they convert it into starch to store energy, which can later be broken down and used when needed, particularly during periods of growth or when sunlight is not available.

Galactose, fructose, and sucrose are all monosaccharides or disaccharides that do not serve as primary energy reserves for plant cells in the same way. While these carbohydrates do play roles in plant metabolism and energy transport, starch is specifically dedicated to energy storage, making it the most relevant answer in this context.