**Core Concept**
Preschool children, typically between 3 to 5 years old, experience a range of physical, emotional, and social changes. Common problems in this age group include developmental delays, behavioral issues, and physical health concerns.

**Why the Correct Answer is Right**
The correct answer will be a problem that is relatively rare or not typically seen in preschool children. This could be an issue more commonly associated with older children or adults.

**Why Each Wrong Option is Incorrect**
**Option A:** Developmental delays are a common concern in preschool children, as they may exhibit delays in cognitive, language, or motor skills.
**Option B:** Behavioral issues such as tantrums, aggression, and non-compliance are also common in preschool children, often related to frustration, testing boundaries, or difficulty with emotional regulation.
**Option C:** Physical health concerns like obesity, diabetes, or cardiovascular disease are less common in preschool children, as these conditions typically develop in older children or adults.

**Clinical Pearl / High-Yield Fact**
Preschool children's brains are still developing, and their prefrontal cortex, responsible for decision-making and impulse control, is not yet fully mature. This can lead to impulsive behaviors and difficulty with self-regulation.

**Correct Answer: C. Physical health concerns like obesity, diabetes, or cardiovascular disease are less common in preschool children, as these conditions typically develop in older children or adults.**