**Core Concept**
Nondepolarizing neuromuscular blockers (NMBs) are a class of medications that inhibit the action of acetylcholine at the neuromuscular junction, leading to muscle paralysis. These agents compete with acetylcholine for binding sites on the nicotinic receptors at the neuromuscular junction.

**Why the Correct Answer is Right**
Nondepolarizing NMBs work by reversibly binding to the nicotinic receptors, preventing the action of acetylcholine. This leads to a competitive antagonism at the neuromuscular junction, resulting in muscle weakness and paralysis. The mechanism of action of nondepolarizing NMBs involves the binding of the drug to the receptor, which prevents the opening of the nicotinic receptor channel and subsequent depolarization of the muscle cell.

**Why Each Wrong Option is Incorrect**
**Option A:** Depolarization of the muscle cell is actually a characteristic of depolarizing NMBs, not nondepolarizing NMBs. Depolarizing NMBs, such as succinylcholine, work by activating the nicotinic receptors, leading to muscle depolarization and paralysis.

**Option B:** Muscle fasciculations are a characteristic of depolarizing NMBs, not nondepolarizing NMBs. Depolarizing NMBs can cause muscle fasciculations due to the initial activation of the nicotinic receptors.

**Option C:** Tachyphylaxis is a characteristic of nondepolarizing NMBs. Nondepolarizing NMBs can cause tachyphylaxis, which is a rapid decrease in the effectiveness of the drug due to receptor desensitization.

**Clinical Pearl / High-Yield Fact**
It is essential to note that nondepolarizing NMBs can cause histamine release, leading to hypotension and bronchospasm. This is a classic exam trap, and students should be aware of the potential side effects of these medications.

**Correct Answer: A. Depolarization of the muscle cell is actually a characteristic of depolarizing NMBs, not nondepolarizing NMBs.**