This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anti-Neoplastic Agents, Subject name: Pharmacology
Anastrazole belongs to which class of drug - 
Select and explain. 
A. Estrogen receptor down regulators (SERDs), B. Selective estrogen receptor modulators (SERMs), C. Selective tissue estrogenic activity regulator (STEAR), D. Aromatase inhibitors
D: Aromatase inhibitors
Answer: D: Aromatase inhibitors 
Explanation: Ans. is 'd' i.e., Aromatase inhibitors Drugs commonly used in hormone (estrogen) receptor positive breast cancero SERMs:- Tamoxifen, tromifeneo SERDs:- Fulvestranto Aromatase inhibitors:- Letrozole, anastrazole, exemestone.