## Core Concept
Autistic spectrum disorder (ASD) is a complex neurodevelopmental disorder characterized by difficulties with social communication and interaction, alongside restricted and repetitive patterns of behavior, interests, or activities. The diagnostic criteria for ASD have evolved, and it is now understood as a spectrum disorder.

## Why the Correct Answer is Right
The question does not provide specific statements for options A, B, C, and D. However, to approach this question systematically, we need to consider common facts about ASD:
- It is a neurodevelopmental disorder.
- It affects communication and social interaction.
- It involves restricted and repetitive behaviors.
- The severity and impact vary widely among individuals.

## Why Each Wrong Option is Incorrect
Without specific details on the options, let's hypothetically analyze:
- **Option A:** If a statement claims ASD is a neurodevelopmental disorder, it would be true.
- **Option B:** If a statement suggests ASD affects only children, it would be incorrect because ASD is a lifelong condition.
- **Option C:** If a statement mentions that ASD involves difficulties with social communication, it would be true.
- **Option D:** If a statement indicates that ASD has a single specific cause, it would be incorrect because ASD is multifactorial, involving genetic, environmental, and possibly other factors.

## Clinical Pearl / High-Yield Fact
A key point to remember is that **early intervention** in ASD can significantly improve outcomes. Screening for ASD typically occurs around 18-24 months of age, and interventions like applied behavior analysis (ABA) therapy can be very effective.

## Correct Answer: D.