The correct answer is option 2: Glycogen. Glycogen is a multibranched polysaccharide of glucose that serves as a form of energy storage in animals and fungi. It is primarily found in the liver and muscle cells of animals. These cells store glycogen to be broken down and converted to glucose when the body needs a quick source of energy.

Let`s take a look at the other options to understand why they are not the correct answer:

- Option 1: Cellulose is also a polysaccharide of glucose, but it serves a structural role in the cell walls of plants, not as a form of energy storage.

- Option 3: Pectin is another type of polysaccharide, but it is primarily found in the cell walls of plants and is involved in cell adhesion.

- Option 4: Chitin is a polysaccharide found in the exoskeletons of arthropods and the cell walls of fungi. It serves a structural role, not as a form of energy storage.

Therefore, the correct answer is option 2: Glycogen.