Azt and valaciclovir are antiviral nucleoside analogs that interfere with
a. cell wall synthesis
b. viral attachment
c. nucleic acid synthesis
d. cell membrane component synthesis
e. protein synthesis

C. Nucleic acid synthesis

Explanation:

AZT, azidothymidine, is an antiviral drug used to check the viral population by blocking the process of reproduction. The azidothymidin is particularly effective against human immunodeficiency virus (HIV) as this drug inhibits the activity of reverse transcriptase which is required for the formation of a DNA copy of the RNA genome of the virus.  

Similarly, Valacyclovir is an antiviral drug that inhibits viral reproduction by blocking the DNA polymerases. The Valacyclovir serves as a prodrug of acyclovir.

the correct option is option a