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It's B. Disruptive mood dysregulation disorder (DMDD).

Explanation: DMDD is a disorder with acute temperamental outbursts on a background of chronic irritability. In contrast, pediatric bipolar disorder exhibits discrete periods of mood disturbance with euphoria, grandiosity, racing thoughts, and lack of need for sleep in a sustained energized state. ODD may be frequently found in children with DMDD. The presence of chronic symptoms of irritability suggests DMDD as opposed to ODD. ADHD may frequently coexist with DMDD but is not characterized by the profound outbursts of temper. Major depressive disorder and dysthymia often have irritability as a prominent clinical symptom but also lack frequent episodes of extreme behavioral dyscontrol.

Muskin PR and Dickerman AL, eds. Study Guide to Psychiatry: A Companion to the American Psychiatric Publishing Textbook of Psychiatry, Sixth Edition. Arlington, VA: American Psychiatric Association Publishing; 2015: 42, 238. Click here to purchase. Members can purchase at a discount.