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
Mechanism of action of actinomycin D is - 
Select and explain. 
A. Inhibits DNA dependent RNA synthesis, B. Activates DNA dependent RNA synthesis, C. Inhibits RNA dependent DNA synthesis, D. Activates RNA dependent DNA synthesis
A: Inhibits DNA dependent RNA synthesis
Answer: A: Inhibits DNA dependent RNA synthesis 
Explanation: Ans. is 'a' i.e.. Inhibits DNA dependent RNA synthesis The anticancer antibiotics are :o Actinomycin - D (Dactinomycin)o Daunorubicin (Rubidomycin)o Mitomycin C* Doxorubicino Mitoxantroneo Mithramycin (plicamvcin)o Bleomycins o These anticancer, antibiotics obtained from micro-organisms and have prominent antitumour activity,o Mechanism of action : They are intercalated betw een DNA strands and interfere w ith its template functionActinomycin "D' inhibits DNA dependent RNA synthesis.Bleomycin cause DNA breakage and free radical formation .Doxo-and daunorubicin inhibit Topoisomerase I & II.Mitomycin acts like alkylating agents.Mitoxantrane binds to DNA to produce strand breakage and inhibits both DNA & RNA synthesis.RememberAll antitumor antibiotics are cell cycle nonspecific except for bleomycin which acts in G2 phase.