Antibiotics do not work against viral infection. Why making antiviral medicine is harder than making antibacterial medicine?

The correct option is B

Virus has only few biochemical mechanisms of their own

Antibiotics commonly block biochemical pathways important for bacteria. These kill the bacteria by inhibiting its growth. But the same antibiotics do not work on viruses, because viruses do not use biochemical pathways such as bacteria and they have few biochemical mechanisms of their own.