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: ENT
Substance associated with minimal tissue reaction in injection laryngoplasty is: 
Select and explain. 
A. Fat, B. Gelfoam, C. Calcium hydroxyapatite, D. Bioplastique
C: Calcium hydroxyapatite
Answer: C: Calcium hydroxyapatite 
Explanation: Injection laryngoplasty uses various materials. The use of calcium hydroxylapatite in this context is a recent development and appears to generate minimal tissue reaction and produce a long-lasting result.