This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Pharmacology
True about tamoxifen is- 
Select and explain. 
A. Selective estrogen receptor downregulator, B. Selective estrogen receptor modulator, C. Selective tissue estrogen activator regulator, D. Estrogen antagonist
B: Selective estrogen receptor modulator
Answer: B: Selective estrogen receptor modulator 
Explanation: Ans. is 'b' i.e., SERM * Has been explained in previous sessions