**Question:** A 14-year-old boy has difficulty expressing himself in writing and makes frequent spelling mistakes, does not follow instruction and cannot wait for his turn while playing a game. He is likely to be suffering from –

A. Attention Deficit Hyperactivity Disorder (ADHD)
B. Dyslexia
C. Autism Spectrum Disorder (ASD)
D. Global developmental delay

**Correct Answer:**

**Core Concept:** The described symptoms in the question are indicative of a neurodevelopmental disorder affecting cognitive and behavioral functions. These symptoms can be categorized into attention, executive function, and social cognition domains.

**Why the Correct Answer is Right:**

The correct answer, **Attention Deficit Hyperactivity Disorder (ADHD)**, is chosen due to the patient's difficulty in attention regulation, impulsivity, and hyperactivity. ADHD is a common neurodevelopmental disorder characterized by persistent inattention, hyperactivity, and impulsivity. The boy exhibits these symptoms, such as making frequent spelling mistakes, not following instructions, and not being able to wait for his turn.

**Why Each Wrong Option is Incorrect:**

A. **Dyslexia:** Although dyslexia may present with reading difficulties, it is unlikely to cause the described global issues, including writing and social cognition, as well as executive function problems.

B. **Autism Spectrum Disorder (ASD):** Although ASD can affect social cognition and executive functions, it typically does not cause hyperactivity and impulsivity. The boy's symptoms align more closely with ADHD.

C. **Global developmental delay:** This term refers to a delay in overall development, including motor skills, social cognition, and intellectual functioning. The symptoms mentioned are more specific to ADHD and do not encompass the full scope of a global developmental delay.

**Clinical Pearl:** Understanding these neurodevelopmental disorders helps in formulating an appropriate treatment plan and providing targeted interventions to improve the boy's quality of life and academic performance. Early diagnosis and intervention can significantly improve outcomes for children with neurodevelopmental disorders.