**Core Concept**
Neuromuscular transmission refers to the process by which nerve impulses are transmitted to skeletal muscle fibers, leading to muscle contraction. This complex process involves the release of neurotransmitters from the motor neuron, binding to receptors on the muscle fiber, and ultimately resulting in muscle contraction.

**Why the Correct Answer is Right**
The correct answer is **Muscarinic Antagonists**. Muscarinic antagonists, such as atropine, block the action of acetylcholine at the neuromuscular junction, thereby inhibiting neuromuscular transmission. This is because muscarinic receptors are involved in the regulation of acetylcholine release and the modulation of the postsynaptic response. By blocking these receptors, muscarinic antagonists reduce the amount of acetylcholine that is released, leading to a decrease in muscle contraction force.

**Why Each Wrong Option is Incorrect**
**Option A:** Succinylcholine is a depolarizing neuromuscular blocking agent that actually facilitates neuromuscular transmission by mimicking acetylcholine.
**Option B:** Beta-2 agonists, such as salbutamol, are used to treat bronchospasm and have no direct effect on neuromuscular transmission.
**Option C:** Local anesthetics, such as lidocaine, block nerve conduction but do not directly affect neuromuscular transmission.

**Clinical Pearl / High-Yield Fact**
Muscarinic antagonists can also cause dry mouth, blurred vision, and urinary retention due to their anticholinergic effects.

**Correct Answer: D. Muscarinic Antagonists**