Which statement best defines Major Depressive Disorder according to DSM-5 criteria?

• A. A depressive mood alone for at least two weeks.
• B. At least five symptoms including depressed mood or anhedonia for at least two weeks, causing impairment.
• C. Persistent sadness for three days.
• D. Mania with psychotic features.

Answer: (C)

The main idea being tested is how Major Depressive Disorder is defined in the DSM-5. For MDD, the diagnosis requires at least five of a list of depressive symptoms occurring during the same two-week period, and at least one of those symptoms must be depressed mood or anhedonia (loss of interest or pleasure). These symptoms must cause clinically significant distress or impairment and cannot be attributable to substances or another medical condition. Examples include depressed mood, diminished interest or pleasure, weight change or appetite disturbance, sleep changes, psychomotor agitation or retardation, fatigue, feelings of worthlessness or excessive guilt, poor concentration, and recurrent thoughts of death.

So the statement that fits DSM-5 criteria is the one describing at least five symptoms, including depressed mood or anhedonia, over a two-week period with impairment. The other options fall short because a single symptom (depressed mood alone), a too-short duration (three days), or symptoms more characteristic of a different condition (mania with psychotic features, as seen in bipolar disorder) do not meet the full criteria for Major Depressive Disorder.