This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Tumors, Subject name: Pathology
Which of the following is NOT a risk factor for endometrial carcinoma? 
Select and explain. 
A. Obesity, B. Nulliparity, C. Smoking, D. Tamoxifen
C: Smoking
Answer: C: Smoking 
Explanation: Endometrial carcinoma:- Type I Type II Age - 55-65 yr - 65-75 yr Finding -Endometrial Hyperplasia - Endometrial Atrophy Risk -E- Estrogen -N-Nulliparity -D-DM/Drugs(Tamoxifen) -O-Obesity - Atrophy - Thin Physique Behavior - Indolent - Spreads lymphatic - Aggressive - Intraperitoneal and lymphatic