Which of the following might indicate major depressive syndrome?

The choice that indicates major depressive syndrome is the loss of interest in activities for extended periods. This symptom is a hallmark of major depressive disorder, reflecting a significant change in the individual's ability to enjoy life and engage in previously pleasurable activities. When someone experiences this loss of interest—often referred to as anhedonia—it suggests that their mental health may be compromised, leading to feelings of emptiness or sadness that persist for an extended duration.

Major depressive syndrome often involves a combination of symptoms that can severely impact a person's everyday life, such as changes in appetite, sleep disturbances, and a general lack of energy. The consistency and duration of losing interest in activities are critical factors, as this symptom often persists for weeks or longer, distinguishing it from transient feelings of sadness or disinterest that can occur in response to specific life events. In contrast, feelings of energy, high motivation, and constant joy are typically indicative of positive mental health and well-being, which are not associated with depressive syndromes.