The correct answer is Diazepam.

- Diazepam is a benzodiazepine that undergoes hepatic metabolism to produce several active metabolites, one of which is desmethyldiazepam (also known as nordiazepam).
- This metabolite has a notably long elimination half-life exceeding 100 hours, which contributes to the prolonged clinical effects of diazepam and impacts dosing intervals.

In contrast:
- Lorazepam is metabolized primarily by conjugation and does not produce active metabolites; it has a shorter half-life.
- Midazolam is metabolized into inactive metabolites and generally has a short elimination half-life.
- Alprazolam is metabolized to inactive compounds and has a moderate half-life but does not form active metabolites like desmethyldiazepam.

This long half-life of desmethyldiazepam can lead to drug accumulation, especially in elderly patients or those with impaired hepatic function, thereby increasing the risk of sedation and other side effects.

Key Points:
- Diazepam is metabolized to the active metabolite desmethyldiazepam.
- Desmethyldiazepam has a half-life exceeding 100 hours.
- This long half-life affects the duration of action and potential drug accumulation.
- Other benzodiazepines like lorazepam, midazolam, and alprazolam do not produce active metabolites with such long half-lives.

Reference: Goodman & Gilman's The Pharmacological Basis of Therapeutics, 13th Edition, Chapter 19: Central Nervous System Depressants and Muscle Relaxants, Page 453-455