Ophthalmoplegic migraine means -
Some guides have given option 'b' as the answer. But you make it clear in your mind that though ophthalmoplegic migraine is more commonly associated with 3rd nerve palsy, according to definition all three nerves can be involved.
"Ophthalmoplegic migrain or episodic ophthalmoplegia is characterized by recurrent attacks of headache associated with paralysis of the third, fourth, and sixth cranial nerves. The incidence of involvement of the third cranial nerve is the most common".
— E. Ahmed.
Headache with irreversible loss of ophthalmic nerve function
Recurrent transient 3rd nerve palsy associated with headache
Headache associated with 3rd, 4th& 6th nerve palsy
Headache associated with optic neuritis