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: Dental
Toxicity of AH26 sealer is due release of 
Select and explain. 
A. Formaldehyde, B. Eugenol, C. Resin acid, D. Gluteraldehyde
A: Formaldehyde
Answer: A: Formaldehyde 
Explanation: None