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: Ophthalmology
A person has restricted eye movements in all directions, ptosis but no squint or diplopia. What is diagnosis: 
Select and explain. 
A. CPEO, B. Multiple cranial nerve palsy, C. Myasthenia gravis, D. Orbital apex syndrome
A: CPEO
Answer: A: CPEO 
Explanation: A i.e. CPEO