47 Which of the following best describes the main idea of this passage?
(A)Coffee has no effect on insomnia.
(B) The smell of coffee helps reduce tension.
(C)Coffee helps keep doctors away.
(D)Caffeine is harmless. 

本文是講述咖啡香氣影響的研究。

雖然已經進行了許多研究來研究飲用咖啡對我們健康的影響，但研究人員剛剛進行了第一項分析咖啡香氣影響的研究。對於許多人來說，早晨喝咖啡只是喚醒睡眠中的腦細胞並使身體處於運轉狀態的東西。但是，根據《農業與食品化學雜誌》第25期，咖啡的氣味對我們的身體也具有類似的影響，甚至更多，從而減少了睡眠不足的影響。至少這是研究人員在老鼠身上發現的。失眠或無法入睡的大鼠被暴露於咖啡味中。咖啡香氣成功激活了大腦中的17個不同基因。其中，已知有13種蛋白質能夠保護神經細胞免受壓力或張力的破壞性影響。那麼，這一發現對那些缺乏睡眠和/或需要熬夜的人來說意味著什麼呢？好吧，也許他們不必花100新台幣買一個通風的拿鐵咖啡，即可在大腦中激活某些基因和/或緩解緊張導致的失眠的影響。他們要做的就是走到拐角處的咖啡店，聞一聞咖啡。

While many studies have been undertaken to study the impact of consuming coffee on our health, researchers have just administered the first study that analyzes the effects of coffee’s aroma. For many people, the morning coffee is just the thing to wake up the dormant brain cells and to put the body in gear. However, according to the 25th issue of the Journal of Agricultural and Food Chemistry, the smell of coffee also has a comparable, if not more, effect on our body, diminishing the impact of sleep deprivation. At least, that’s what researchers have found in rats. Rats that suffered from insomnia, or inability to sleep, were exposed to the smell of coffee. Coffee aroma successfully activated seventeen different genes in their brains; among them, thirteen were known to produce proteins that protect nerve cells from the damaging impact of stress or tension. So, what is the implication of this finding for those people who were stressed by lack of sleep and/or need to stay up late? Well, maybe they do not have to shell out 100 NT dollars for a venti-sized latte to get some of their genes activated in their brains and/or to ease the impact of sleeplessness resulting from tension. All they need to do is to walk to a coffee shop around the corner and get a sniff of coffee.

47以下哪項最能描述這段經文的主要思想？

（B）咖啡的氣味有助於減輕壓力。

Well, maybe they do not have to shell out 100 NT dollars for a venti-sized latte to get some of their genes activated in their brains and/or to ease the impact of sleeplessness resulting from tension. All they need to do is to walk to a coffee shop around the corner and get a sniff of coffee.

好吧，也許他們不必花100新台幣買一個通風的拿鐵咖啡，即可在大腦中激活某些基因和/或緩解緊張導致的失眠的影響。他們要做的就是走到拐角處的咖啡店，聞一聞咖啡。