This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Disorders of menstruation, Subject name: Gynaecology & Obstetrics
[{'content': 'Lactional amenorrhea is due to \nSelect and explain. \nA. Prolactin induced inhibition of GnRH, B. Prolactin induced inhibition of FSH, C. Oxytocin induced inhibition of GnRH, D. Oxytocin induced inhibition of FSH', 'role': 'user'}, {'content': 'Answer: A \nExplanation: High levels of prolactin inhibits GnRH release from Hypothalamus and thus indirectly FSH and LH secretion from anterior pituitary Reference: Textbook of Gynaecology; Sheila balakrishnan; 2nd edition; Page no 27', 'role': 'assistant'}]