Final answer:
The correct answer is d. glycogen, which is the storage form of glucose in humans and animals, characterized by its highly branched structure to optimize energy release when needed.
Step-by-step explanation:
The storage form of carbohydrates in humans and other animals is d. glycogen.
Glycogen is the main storage form of glucose in animals and humans, similar to how plants use starch for the same purpose. Glycogen consists of glucose monomers and is a highly branched molecule, mainly stored in the liver and muscle cells. When the body needs energy, or when blood glucose levels fall, glycogen undergoes a process called glycogenolysis where it is broken down to release glucose into the bloodstream.
In comparison, starch, which is composed of amylose and amylopectin, serves as the energy storage in plants. While amylose is a linear chain of glucose units, amylopectin and glycogen are branched, with glycogen being more extensively branched than amylopectin, which is an important factor in how quickly it can be broken down to meet energy demands.