1. The problem statement, all variables and given/known data The activity of drugs 1 to 5 is given as follows: Drug #1: blocks RNA-dependent RNA polymerases Drug #2: blocks DNA-dependent RNA polymerases Drug #3: blocks RNA-dependent DNA polymerases Drug #4: blocks DNA-dependent DNA polymerases Drug #5: blocks ribosomes Using this information, answer the following questions: a) Which of these drugs blocks human host cells? Why? b) Which drug is feasible to block retroviruses? Why? c) Which of the drugs is completely ineffective for human host cells? 2. Relevant equations Don't know if equation is required here. 3. The attempt at a solution Drug 3 would be suitable for b option since retrovirus by reverse transcriptase make DNA out of RNA. For a) part I am not getting what it means by human host cell here and relation.