## Core Concept
The question pertains to a psychological or psychiatric condition manifesting in children, specifically at the age of 2.5 years, characterized by nighttime episodes of screaming with fear. This scenario is suggestive of a disorder related to sleep or anxiety.

## Why the Correct Answer is Right
The correct answer, **Night Terrors (Sleep Terrors)**, is a type of sleep disorder that involves getting up and walking around in a state of extreme fear, panic, or anxiety. These episodes typically occur during deep sleep (slow-wave sleep) and often happen in the first third of the night. Children experiencing night terrors may scream, thrash about, and be inconsolable, but they usually do not respond to comfort and do not remember the episode in the morning. Night terrors are more common in children aged 2-5 years, which aligns with the age provided in the question.

## Why Each Wrong Option is Incorrect
- **Option A:** Without a specific option provided, we cannot directly address its inaccuracies. However, common incorrect options might include conditions like sleepwalking (which can occur but doesn't fully encapsulate the fear and screaming aspect), nightmares (typically occur in REM sleep, later in the night, and the child can usually recall the dream), or other anxiety disorders (which might present differently and not specifically tied to nighttime).

- **Option B:** Similarly, without specifics, we assume any provided option does not accurately describe night terrors or is less directly related to the specific clinical presentation described.

- **Option C:** Again, lacking details, but if another sleep disorder or psychiatric condition is listed, it might not match the age of onset, the specific symptoms, or the typical presentation.

## Clinical Pearl / High-Yield Fact
A key point to remember is that **night terrors** are distinct from nightmares. Night terrors occur during deep sleep, are more common in young children, and the child usually does not recall the episode. They are often triggered by factors like sleep deprivation, stress, or fever. Parents are advised to ensure the child's safety during an episode and not attempt to wake them, as this can lead to increased agitation.

## Correct Answer Line
**Correct Answer: D. Night Terrors.**