This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
A 49-year-old man comes to the physician because of a history of recurrent attacks of drowsiness, sweating, and palpitations. His blood glucose level during one of the episodes is 52 mg/dL. Recovery occurs in response to intravenous 10% dextrose C-peptide levels are below the normal range. 
Which of the following is the most likely diagnosis? 
Select and explain. 
A. Factitious insulin use, B. Gastrinoma, C. Glucagonoma, D. Insulinoma
A: Factitious insulin use
Answer: A: Factitious insulin use 
Explanation: None