**Core Concept**
The question tests the student's knowledge of **neuromuscular blockers**, specifically their pharmacokinetic properties. Neuromuscular blockers are used in anesthesia to facilitate tracheal intubation and provide muscle relaxation during surgery.

**Why the Correct Answer is Right**
The correct answer is related to the drug's onset and duration of action. The shortest acting neuromuscular blocker is **succinylcholine**, also known as **suxamethonium**, which has a rapid onset of action and a short duration of action due to its rapid hydrolysis by **plasma cholinesterase**.

**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because it is not specified.
**Option B:** Incorrect because it is not specified.
**Option D:** Incorrect because it is not specified.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that **succinylcholine** has a rapid onset and short duration, making it ideal for rapid sequence intubation. However, it is also associated with **hyperkalemia** as a potential side effect.

**Correct Answer:** D. Succinylcholine.