What is a key characteristic of depression?

Prolonged feelings of sadness are a hallmark characteristic of depression. This mental health condition is often defined by persistent low mood that lasts for an extended period, affecting a person's ability to function in daily life. Individuals experiencing depression may find that these feelings of sadness are not just temporary but can linger for weeks, months, or even longer without significant relief. This chronic state of sadness can also be accompanied by other symptoms, such as fatigue, changes in appetite, feelings of worthlessness, and difficulty concentrating.

The other options describe experiences that are not typical of depression; increased energy levels are generally associated with elevated mood or manic states, heightened mood swings may indicate bipolar disorder rather than depression, and delusions of grandeur are more characteristic of certain psychotic disorders or manic phases. Therefore, the presence of prolonged feelings of sadness accurately captures a fundamental aspect of depression.