The correct option is D Alzheimer's disease
Choline acetyltransferase is a transferase enzyme responsible for the synthesis of the neurotransmitter acetylcholine. The Alzheimer's disease involves difficulty in memory and recognition. The concentrations of acetylcholine and choline acetyltransferase are remarkably reduced in the cerebral neocortex and hippocampus.
Thus, the correct answer is the option (D), 'Alzheimer's disease'.