Answer:
The correct answer will be option D.
Explanation:
Pathogen-associated molecular patterns or PAMPs are the structural molecular motifs present in the microbes.
These molecules activate the immune system after they are recognized by the pattern recognition receptors and toll-like receptors. The host activates its immune system in response and becomes resistant to the pathogen.
If mutation takes place in the conserved sequence of the PAMP, they will not be recognized by the host and the host will not be able to trigger its immune response.
Thus, option D is the correct answer.