Choose the characteristics of vancomicin:
a) It is a glycopeptide, inhibits cell wall synthesis active only against Gram-negative bacteria
b) It is a glycopeptide, that alters permeability of cell membrane and is active against anaerobic bacteria
c) It is a beta-lactam antibiotic, inhibits cell wall synthesis active only against Pseudomonas aeruginosa
d) It is a glycopeptide, inhibits cell wall synthesis and is active only against Gram-positive bacteria.
