Which of the following is a common symptom of attention deficit hyperactivity disorder (ADHD)?

Impulsivity is a hallmark symptom of attention deficit hyperactivity disorder (ADHD). Individuals with ADHD often exhibit difficulties in self-control, which can manifest in impulsive behaviors such as acting without thinking, interrupting others, or making hasty decisions without considering the consequences. This impulsivity can significantly affect various aspects of life, including social interactions and academic performance.

In contrast, while increased appetite, drowsiness, and disinterest in school may be observed in some individuals, they are not defining characteristics of ADHD. Increased appetite is more commonly associated with other conditions or medications rather than ADHD itself. Drowsiness can result from a variety of factors, including medications or sleep disorders, but is not indicative of ADHD. Disinterest in school can be related to a range of issues, including learning disabilities, but is not a core symptom of ADHD like impulsivity is.