question: Q:A 42-year-old, G3P2012 woman comes to the clinic complaining of painful menstruation for the past 4 months. She is also using more tampons compared to prior periods. She is concerned as her close friend was just diagnosed with endometrial cancer. Prior to these symptoms, her menstrual cycle was regular (every 28 days) and without pain. She denies abnormal uterine bleeding, abnormal discharge, past sexually transmitted diseases, or spotting. A bimanual pelvic examination is unremarkable except for a mobile, diffusely enlarged, globular uterus. What is the most likely explanation for this patient’s symptoms?? 
  {'A': 'Abnormal endometrial gland proliferation at the endometrium', 'B': 'Benign smooth muscle tumor within the uterine wall', 'C': 'Collection of endometrial tissue protruding into the uterine cavity', 'D': 'Invasion of endometrial glands into the myometrium', 'E': 'Non-neoplastic endometrial tissue outside of the endometrial cavity'},