Seasonal Affective Disorder is a disturbance of mood and behavior accompanied by at least 5 key features for at least 2 weeks.

Choice A reason: Seasonal Affective Disorder (SAD) is a subtype of major depressive disorder with a seasonal pattern, requiring at least two major depressive episodes in a seasonal pattern over two years, not necessarily five key features for two weeks. The diagnostic criteria involve symptoms like low mood, anhedonia, and fatigue, but the two-week duration with five symptoms applies to major depression generally, not specifically SAD, which emphasizes seasonal recurrence. Choice B reason: The statement is false because Seasonal Affective Disorder is defined by recurrent depressive episodes tied to specific seasons, typically winter, rather than a strict requirement of five key features for two weeks. SAD involves symptoms like hypersomnia and carbohydrate craving, but the diagnostic focus is on the seasonal pattern, not the exact symptom count or duration stated.