my answer to this question is B. i hope that i helped you.
Answer:
Bacterial infections
Explanation:
Peptidoglycan also called as murein is a polymer which makes up the bacterial cell wall. It consists of sugars and amino acids. Sugar component is made of alternating NAM (N acetyl muramic acid) and NAG (N acetyl glucosamine) residues. A peptide of three to five amino acids is attached to NAM. The peptide chains often cross link with each other to form a strong mesh like structure.
If a drug degrades peptidoglycan structure, bacterial cell wall will not form. As a result it will not be able to survive and ultimately the infection will be cleared up. Example of such drugs are vancomycin, ramoplanin, bleomycin etc.
It is called dentin. It lies beneath the enamel and the cementum, and makes up the majority of the tooth.