The process that does NOT happen when breaking down glucose is "Cells reproducing through budding."
The other processes listed—digestion, absorption, and cellular respiration—are all involved in the breakdown and utilization of glucose by the body. Digestion breaks down food into simpler molecules, absorption allows those molecules to enter the bloodstream, and cellular respiration is the process by which cells use glucose to produce energy. However, budding is a method of asexual reproduction in some organisms and is not directly related to the breakdown of glucose.