Final answer:
The most common cause of a bloody nipple discharge is an intraductal papilloma, a benign tumor in a breast duct. Breast cancer also causes similar symptoms, hence medical consultation is suggested for accurate diagnosis.
Step-by-step explanation:
The most common cause of a bloody nipple discharge is 3) Intraductal papilloma. An intraductal papilloma is a small, benign tumor that forms in a milk duct in the breast. It's an important condition to be aware of, as it can sometimes be mistaken for something more serious due to its symptom of bloody discharge. Nonetheless, conditions like breast cancer can also cause similar symptoms. If a person has a bloody nipple discharge, they should consult a healthcare professional for proper diagnosis and treatment. Conditions such as breast infection, fibrocystic changes, and cancers have unique symptoms like unusual bleeding or discharge, a lump in the breast, chronic indigestion or difficulty swallowing, obvious changes in a wart or mole, and persistent coughing or hoarseness, all of which require medical attention.