**Core Concept**
The question is testing the knowledge of nondepolarizing muscle relaxants, specifically their duration of action. Nondepolarizing muscle relaxants are a class of medications that block the action of acetylcholine at the neuromuscular junction, leading to muscle relaxation.

**Why the Correct Answer is Right**
The shortest acting nondepolarizing muscle relaxant is Vecuronium. Vecuronium is a competitive antagonist of acetylcholine at the nicotinic receptors of the neuromuscular junction. It has a rapid onset of action, with peak effect occurring within 2-3 minutes, and its duration of action is approximately 15-20 minutes. This short duration of action makes Vecuronium ideal for use in rapid sequence intubation and in patients with compromised respiratory function.

**Why Each Wrong Option is Incorrect**
**Option A:** Rocuronium is a nondepolarizing muscle relaxant, but it has a longer duration of action than Vecuronium, typically lasting around 30-40 minutes.
**Option B:** Atracurium is another nondepolarizing muscle relaxant, but it also has a longer duration of action, typically lasting around 20-30 minutes.
**Option C:** Mivacurium is a short-acting nondepolarizing muscle relaxant, but it is not as short-acting as Vecuronium, with a duration of action typically lasting around 15-25 minutes.

**Clinical Pearl / High-Yield Fact**
Vecuronium is often used in combination with other medications to enhance its effects, such as succinylcholine to facilitate rapid sequence intubation.

**Correct Answer:** C. Vecuronium