题目内容：
根据下面资料，回答 Millions of Americans lie awake at night counting sheep, or have a stiff drink or pop an allergy pill, hoping it will make them drowsy. But experts agree all that self-medicating is a bad idea, and the causes of chronic insomnia remain mysteriou
A.Walking around in a fog. B.Lack of energy. C.Nap irregularly. D.Cognitive functions loss.
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