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 40-year-old lady with temporal field defects and galactorrhoea is most likely to have - 
Select and explain. 
A. Pituitary macroadenoma, B. Craniopharyngioma, C. Lactational failure, D. Pregnancy
A: Pituitary macroadenoma
Answer: A: Pituitary macroadenoma 
Explanation: Temporal field defects in women with galactorrhoea suggests pituitary macroadenoma.
Increased secretion of prolactin causes amenorrhoea, galactorrhoea and the mass effect of the tumour on the optic nerve produces headache and visual field defect.