This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cranial Nerve Disorders, Subject name: Medicine
A 35-year-old male with bilateral asymmetrical ptosis and diplopia on watching TV or working on a laptop.Which test will be useful for diagnosis? 
Select and explain. 
A. Nerve conduction velocity, B. Ice pack test, C. Muscle biopsy, D. CPK- MM Levels
B: Ice pack test
Answer: B: Ice pack test 
Explanation: Ans. (b) Ice pack test.The image shows presence of asymmetrical droopy eyelids with history of development of this finding on repeated working of eye muscles. The possible diagnosis is myasthenia gravis which can be identified by Ice pack test.Image source - style="font-family: Times New Roman, Times, serif">