**Core Concept**
Muscle relaxants with ganglion blocker action are a class of medications that simultaneously relax skeletal muscles and block the transmission of nerve impulses at the autonomic ganglia. This dual action is useful in certain clinical situations, such as managing muscle spasms and hypertension. The ganglion blockers inhibit the release of acetylcholine from the preganglionic neurons, thereby reducing sympathetic tone.

**Why the Correct Answer is Right**
The correct answer is a medication that combines a non-depolarizing muscle relaxant with a ganglion blocker. This combination allows for the relaxation of skeletal muscles and a reduction in blood pressure. The ganglion blocker, typically a quaternary ammonium compound, selectively blocks the nicotinic acetylcholine receptors at the autonomic ganglia, preventing the transmission of sympathetic nerve impulses. This action reduces the release of catecholamines, leading to decreased blood pressure and heart rate.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the medication listed does not have a known ganglion blocker action. It may be a muscle relaxant, but it does not possess the additional mechanism of ganglion blockade.

**Option B:** This option is incorrect because the medication listed is a depolarizing muscle relaxant, which works by activating nicotinic receptors at the neuromuscular junction, rather than blocking them at the autonomic ganglia.

**Option C:** This option is incorrect because the medication listed is an anticholinesterase, which increases acetylcholine levels at the neuromuscular junction, rather than blocking its release at the autonomic ganglia.

**Option D:** This option is incorrect because the medication listed is a beta-blocker, which reduces sympathetic tone by blocking beta-adrenergic receptors, rather than blocking the transmission of nerve impulses at the autonomic ganglia.

**Clinical Pearl / High-Yield Fact**
When choosing a muscle relaxant, consider the patient's blood pressure and autonomic tone. Muscle relaxants with ganglion blocker action, such as gallamine, can be useful in managing hypertension and muscle spasms. However, they can also cause hypotension and bradycardia, so careful monitoring is necessary.

**Correct Answer: D. Atracurium.**