**Core Concept**
Non-depolarizing muscle relaxants (NDMRs) are a class of medications that competitively inhibit the action of acetylcholine at the neuromuscular junction, leading to muscle relaxation. They are commonly used in anesthesia to facilitate endotracheal intubation, surgical procedures, and mechanical ventilation.

**Why the Correct Answer is Right**
Non-depolarizing muscle relaxants work by binding to the nicotinic acetylcholine receptor (nAChR) at the neuromuscular junction, preventing acetylcholine from binding and triggering muscle contraction. This competitive inhibition results in a decrease in muscle tone and eventually paralysis. The mechanism of action of NDMRs is reversible, meaning that if the muscle relaxant is removed, the muscle will return to its normal function.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because NDMRs do not depolarize muscle cells; instead, they competitively inhibit acetylcholine at the neuromuscular junction.
* **Option B:** This option is incorrect because NDMRs do not act by increasing the release of acetylcholine; they work by blocking the action of acetylcholine at the neuromuscular junction.
* **Option C:** This option is incorrect because NDMRs do not have a direct effect on the central nervous system; their action is limited to the neuromuscular junction.

**Clinical Pearl / High-Yield Fact**
Non-depolarizing muscle relaxants can cause histamine release, leading to hypotension, bronchospasm, and cutaneous flushing. This is particularly relevant in patients with a history of allergies or asthma.

**Correct Answer:** A.