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: Microbiology
Quellung reaction is due to - 
Select and explain. 
A. Capsular swelling, B. Mitochondrial swelling, C. RBC swelling, D. Ribosomal swelling
A: Capsular swelling
Answer: A: Capsular swelling 
Explanation: Ans. is 'a' i.e., Capsular swelling