Final answer:
Amphotericin B disrupts the cytoplasmic membranes of fungi by targeting the synthesis of ergosterol, a sterol found in fungal cell membranes but not in human cells.
Step-by-step explanation:
Amphotericin B is an antifungal drug that disrupts the cell membrane of fungi. It targets the synthesis of ergosterol, a sterol found in fungal cell membranes but not in human cells. By interfering with ergosterol synthesis, Amphotericin B selectively damages fungal cell membranes, making it toxic to fungi.
Therefore, the correct answer is A) disruption of cytoplasmic membranes.