A Small Percentage of People with Bipolar Disorder Display Rapid

A small percentage of people with bipolar disorder display rapid cycling, which is characterized by:

A) four or more manic or depressive episodes every year.
B) thoughts that shift rapidly and loosely from topic to topic.
C) an inability to initiate or persist in even simple forms of goal-directed behavior.
D) flat affect and a dramatic reduction in emotional responsiveness and facial expressions.