This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: DNB 2018, Subject name: Pharmacology
Which of the following drug is specifically for Her 2 positive breast carcinoma is: 
Select and explain. 
A. Trastuzumab, B. Tamoxifen, C. Exemestane, D. Fulvestrant
A: Trastuzumab
Answer: A: Trastuzumab 
Explanation: Monoclonal antibody against HER2/neu receptor are:- Trastuzumab Peuzumab S/E:- Cardiotoxic Tamoxifen:- Antagonist on estrogen receptor expressed in mammary tissue. - Agonist on estrogen receptor in bone - Useful not only in treatment and prophylaxis of breast cancer but also in prevention of osteoporosis Exemestane:- a steroid molecule, irreversible inhibitor of aromatase(enzyme required for estrogen synthesis) Fulvestrant:- Pure estrogen receptor antagonist(Selective estrogen receptor down regulator)