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
Best disinfectant for endoscopes is: 
Select and explain. 
A. Hypochlorite, B. Formaldehyde, C. Glutaraldehyde, D. Chlorhexidine
C: Glutaraldehyde
Answer: C: Glutaraldehyde 
Explanation: Activated 2% alkaline glutaraldehyde is used for decontaminating flexible endoscopes.
Advantages

 Relatively non-corrosive
 Will kill spores with prolonged exposure (3- 10 hours). 

Disadvantages
Toxic. Irritant. 
Possible alternatives:

 Ortho-phthalaldehyde (OPA) peracetic acid.
 Chlorine dioxide (ClO2) products (such as Tristel).
 Super-oxidized water (Sterilox).

Advantages of these newer agents are - rapidly sporicidal, mycobactericidal and viricidal. BUT remember - No agent is clearly superior to the others and a thorough assessment needs to be performed before an alternative agent is chosen.