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: Medicine
A 35 year old lady Malti has unilateral headache, nausea, vomiting and visual blurring. The diagnosis is - 
Select and explain. 
A. Cluster headache, B. Glaucoma, C. Subarachnoid haemorrhage, D. Posterior fossa cyst
B: Glaucoma
Answer: B: Glaucoma 
Explanation: None