This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General pharmacology, Subject name: Pharmacology
In which phase of clinical trials, post-marketing surveillance of a drug is carried out 
Select and explain. 
A. Phase I, B. Phase II, C. Phase III, D. Phase IV
D: Phase IV
Answer: D: Phase IV 
Explanation: Clinical trials divided into 4 phases Phase I: Human pharmacology and safety Phase II: Therapeutic exploration and dose ranging Phase III: Therapeutic confirmation/comparison Phase IV* Postmarketing surveillance/studies-during this phase or after the release of the drug into the market, ADRs are monitored through pharmacovigilance centers. Ref ;KD Tripathi pharmacology 7 th edition (page no; 80)