Attention Deficit/Hyperactivity Disorder (ADHD) is characterized by...

Attention Deficit/Hyperactivity Disorder (ADHD) is primarily characterized by a persistent pattern of inattention and impulsivity, which is reflected in the correct answer. Individuals with ADHD may have difficulty sustaining attention, organizing tasks, following through on instructions, and managing time effectively. This inattention can lead to challenges in academic settings and everyday functioning. Impulsivity in ADHD can manifest as difficulty waiting for a turn, interrupting others, and making hasty decisions without considering the consequences.

In contrast, other options describe symptoms and characteristics associated with different mental health disorders. Intense fear of gaining weight relates to eating disorders such as anorexia nervosa, severe mood disturbances are indicative of mood disorders like bipolar disorder or major depressive disorder, and delusions and hallucinations are symptoms commonly found in psychotic disorders such as schizophrenia. Thus, the defining features of ADHD distinctly align with inattention and impulsivity, making the first option the correct choice.