**Core Concept**
Parasomnias are a group of sleep disorders that involve abnormal movements or behaviors during sleep, such as sleepwalking, sleep talking, or nightmares. These conditions can occur during the non-rapid eye movement (NREM) or rapid eye movement (REM) stages of sleep.

**Why the Correct Answer is Right**
The correct answer will be a condition that does not fit within the parasomnia category. Parasomnias typically involve complex behaviors or movements that occur during sleep, often with a loss of consciousness or impaired self-awareness. To determine which option is not a parasomnia, we need to examine each choice and its characteristics.

**Why Each Wrong Option is Incorrect**
**Option A:** Sleepwalking (somnambulism) is a classic example of a parasomnia, characterized by complex behaviors such as walking or performing other actions during deep NREM sleep.
**Option B:** Sleep talking (somniloquy) is also a parasomnia, involving vocalizations during sleep that can range from simple sounds to complex conversations.
**Option C:** Narcolepsy is a neurological disorder that affects the brain's ability to regulate sleep-wake cycles, but it is not typically classified as a parasomnia. Narcolepsy involves excessive daytime sleepiness, cataplexy (sudden muscle weakness), and other symptoms that are distinct from parasomnias.

**Clinical Pearl / High-Yield Fact**
The International Classification of Sleep Disorders (ICSD) categorizes parasomnias into several subtypes, including sleepwalking, sleep talking, and sleep terrors. Recognizing the differences between these conditions is essential for accurate diagnosis and treatment.

**Correct Answer:** C. Narcolepsy