118. According to a review of 61 studies of patients suffering from severely debilitating depression, a large majority of the patients reported that missing a night’s sleep immediately lifted their depression. Yet sleep-deprivation is not used to treat depression even though the conventional treatments, which use drugs and electric shocks, often have serious side effects.

Which of the following, if true, best explains the fact that sleep-deprivation is not used as a treatment for depression?

(A) For a small percentage of depressed patients, missing a night’s sleep induces a temporary sense of euphoria.

(B) Keeping depressed patients awake is more difficult than keeping awake people who are not depressed.

(C) Prolonged loss of sleep can lead to temporary impairment of judgment comparable to that induced by consuming several ounces of alcohol.

(D) The dramatic shifts in mood connected with sleep and wakefulness have not been traced to particular changes in brain chemistry. E

(E) Depression returns in full force as soon as the patient sleeps for even a few minutes.

麻烦问下这里sleep-deprivation是什么意思呢，究竟是睡眠还是睡眠剥夺，如果是睡眠剥夺，那怎么可能还选E呢？
希望大家提出自己的看法。