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: Unknown
Antimicrobial resistance in frequent lens user is due to- 
Select and explain. 
A. Biofilm formation, B. Improper handling, C. Unhygienic formation, D. Low potency of antibiotics
A: Biofilm formation
Answer: A: Biofilm formation 
Explanation: (Refer: AK Khurana Comprehensive Ophthalmology, 6th edition, pg no. 50)

The contaminated contact lens provides Psuedomonas aeruginosa an idea site for attachment and biofilm production
Continuous contact of the eye to the biofilm-infested lens can lead to serious ocular diseases, such as keratitis (corneal ulcers)
The biofilm also prevent effective penetration of the antibiotics, which increase the chances of antibiotic resistance