This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.
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Question: Serotonin is a neuromodulator involved in regulation of mood and behavior. Development in the limbic system plays an important role in determining rewards and punishments and processing emotional experience and social information. Changes in the levels of the neurotransmitters dopamine and serotonin in the limbic system make adolescents more emotional and more responsive to rewards and stress. The corresponding increase in emotional variability also can increase adolescents' vulnerability. The effect of serotonin is not limited to the limbic system: Several serotonin receptors have their gene expression change dramatically during adolescence, particularly in the human frontal and prefrontal cortex .

Answer: Which neuromodulator is involved in regulation of mood and behavior?


Question: While on one hand the Heian period was an unusually long period of peace, it can also be argued that the period weakened Japan economically and led to poverty for all but a tiny few of its inhabitants. The control of rice fields provided a key source of income for families such as the Fujiwara and were a fundamental base for their power. The aristocratic beneficiaries of Heian culture, the Ryōmin (良民 "Good People") numbered about five thousand in a land of perhaps five million. One reason the samurai were able to take power was that the ruling nobility proved incompetent at managing Japan and its provinces. By the year 1000 the government no longer knew how to issue currency and money was gradually disappearing. Instead of a fully realised system of money circulation, rice was the primary unit of exchange. The lack of a solid medium of economic exchange is implicitly illustrated in novels of the time. For instance, messengers were rewarded with useful objects, e.g., an old silk kimono, rather than paid a fee.

Answer: What crop was a primary source of income during the Heian period?


Question: The Republic of Letters was the sum of a number of Enlightenment ideals: an egalitarian realm governed by knowledge that could act across political boundaries and rival state power. It was a forum that supported "free public examination of questions regarding religion or legislation". Immanuel Kant considered written communication essential to his conception of the public sphere; once everyone was a part of the "reading public", then society could be said to be enlightened. The people who participated in the Republic of Letters, such as Diderot and Voltaire, are frequently known today as important Enlightenment figures. Indeed, the men who wrote Diderot's Encyclopédie arguably formed a microcosm of the larger "republic".

Answer:
What did the Republic of Letters support?