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: Pharmacology
One of the obvious consequences of alchol (ethanol), ingestion in many individuals is facial flushing and increased heart rate triggered off by alcohol getting metabolized to 
Select and explain. 
A. Formaldehyde, B. Acetaldehyde, C. Propanaldehyde, D. Butanaldehyde
B: Acetaldehyde
Answer: B: Acetaldehyde 
Explanation: None