This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Ophthalmology
Which of the following is/are the side effect of using argon laser- 
Select and explain. 
A. Hypopigmentation, B. Crusting, C. Keloid formation, D. All the above
D: All the above
Answer: D: All the above 
Explanation: Argon Laser *Wavelength 488-514 nm *Penetration depth of 1mm, which can be increased by cooling. *Side effects: crusting and possible blistering of skin, irreversible hypopigmentation, transient hyperpigmentation, punctate atrophic or hyperophic scars, keloid formation. Ref: Lasers in otolaryngology by Karl bernd p.144