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
Which of the following structures, found external
to the bacterial cell wall, are involved in bacterial
attachment to cell surfaces? 
Select and explain. 
A. Capsule, B. Flagella, C. Pill, D. Mesosomes
C: Pill
Answer: C: Pill 
Explanation: None