Question

What is the main reason that antiviral drugs often fail when tested?
1.
The drugs often cause cancerous tumours 2.The drugs prove toxic to certain human cells 3.The viruses join to the cell walls to survive 4.The viruses mutate far too rapidly each time

Answer 1

4.Viruses adapt to antiviral drugs and become more powerful

Answer 2

4 one is true he is right