The correct answer is option 4, Glucose. Glucose is a simple sugar that is easily broken down and absorbed by the body for quick energy release. It is the main source of energy for our cells and is utilized by the body in various metabolic processes. Lactose, option 1, is a sugar found in milk and needs to be broken down by the enzyme lactase before it can be absorbed and used for energy. Cellulose, option 2, is a complex sugar found in the cell walls of plants and is not digestible by humans, so it does not provide readily available energy. Maltose, option 3, is a disaccharide made up of two glucose molecules and is broken down into glucose by the body. However, glucose itself is the simplest and most readily available form of sugar for energy production.