In a lady with bilateral superior temporal quadrantopia, galactorrhea, the most probable cause is:

Answer is A (Pituitary Macroadenoma): Presence of galactorrhea (hyperprolactinemia) and bitemporal superior quadrantopia (visual field defect) is consistent with a diagnosis of pituitary macroadenoma. Both non secretory pituitary Macroadenoma and prolactin secreting Macroadenoma (Large Prolactinoma) may produce the above manifestation.