Which of the following is NOT listed as a type of depression?

• A. Dysthymia
• B. Major depression
• C. Bipolar disorder
• D. Seasonal affective disorder

Answer: (D)

Depressive disorders are categorized by how and when the symptoms show up. Dysthymia, or persistent depressive disorder, is a long-lasting, milder form of depression. Major depressive disorder involves significant, marked depressive episodes. Bipolar disorder is a mood disorder that includes depressive episodes but is classified separately, since it also features periods of elevated or irritable mood.

Seasonal affective disorder describes depressive symptoms that occur in a specific season, most often winter. In many classification systems, this seasonal pattern is considered a specifier that can accompany major depressive disorder or bipolar disorder rather than a standalone type of depression. That’s why it’s not listed as a separate type of depression in those frameworks, making it the best choice for the statement that it is not listed as a type of depression.