Which of the following statements is/are true regarding diazepam?
1. Its long duration of action is partly due to active metabolites.
2. It does not produce antianxiety effects after intramuscular administration.
3. Intravenous administration is more reliable than oral.
4. Its sedative effect can be reversed by naloxone.

(1) and (3)

(1) (2) (3)

(2) and (4)

(4) only

All of the above.