What is one common symptom of schizophrenia?

Delusions are a common symptom of schizophrenia, which is a severe mental disorder characterized by disruptions in thought processes, perceptions, emotional responsiveness, and social interactions. Delusions involve strongly held beliefs that are inconsistent with reality. For example, an individual might believe they are being persecuted or that they have extraordinary abilities, despite evidence to the contrary. This symptom can significantly impair the individual's ability to function in daily life and affects how they interact with the world around them.

In contrast, while mood swings, anxiety, and hyperactivity can be associated with various mental health disorders, they are not characteristic symptoms of schizophrenia itself. Mood swings are more closely linked to mood disorders, anxiety is a common feature of various anxiety disorders, and hyperactivity is often seen in attention-deficit/hyperactivity disorder (ADHD). Therefore, delusions stand out as a core feature of schizophrenia, making it the correct answer in this context.