This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology and breast, Subject name: Anatomy
Which of the following indicate Ca breast 
Select and explain. 
A. Ulceration of nipple, B. Cracked nipple, C. Serous discharge, D. Recent retraction of nipple
D: Recent retraction of nipple
Answer: D: Recent retraction of nipple 
Explanation: Recent retraction of the nipple may be of considerable pathological significance. A slit-like retraction of the nipple may be due to duct ectasia and chronic periductal mastitis, but circumferential retraction, with or without an underlying lump, may well indicate an underlying Ca. Although ulceration of nipple may occur in Ca breast but may occur in other conditions also. The cracked nipple may occur during lactation and be the forerunner of acute infective mastitis. Various degrees of cellular and architectural atypia (Atypical hyperplasia) occurs in 'Ca in situ' and 'breast Ca'. ref - Internet