You are answering a USMLE-style medical question. Question: A clinical researcher is interested in creating a new drug for HIV patients. Darunavir has been particularly efficacious in recent patients; however, some have experienced an increased incidence of hyperglycemia. A new drug called DN501 is developed with the same mechanism of action as darunavir but fewer side effects. Which of the following is the mechanism of action of DN501? Options: A) Prevents viral transcription B) Inhibits viral assembly C) Inhibits viral entry D) Prevents T-cell binding Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.