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.

Input: Consider Input: The Delhi Metro is a rapid transit system serving New Delhi, Delhi, Gurgaon, Faridabad, Noida, and Ghaziabad in the National Capital Region of India. Delhi Metro is the world's 12th largest metro system in terms of length. Delhi Metro was India's first modern public transportation system, which had revolutionised travel by providing a fast, reliable, safe, and comfortable means of transport. The network consists of six lines with a total length of 189.63 kilometres (117.83 miles) with 142 stations, of which 35 are underground, five are at-grade, and the remainder are elevated. All stations have escalators, elevators, and tactile tiles to guide the visually impaired from station entrances to trains. It has a combination of elevated, at-grade, and underground lines, and uses both broad gauge and standard gauge rolling stock. Four types of rolling stock are used: Mitsubishi-ROTEM Broad gauge, Bombardier MOVIA, Mitsubishi-ROTEM Standard gauge, and CAF Beasain Standard gauge.

Output: What is the total length of the Delhi Metro?


Input: Consider Input: Research seems to favor the hypothesis that adolescents and adults think about risk in similar ways, but hold different values and thus come to different conclusions. Some have argued that there may be evolutionary benefits to an increased propensity for risk-taking in adolescence. For example, without a willingness to take risks, teenagers would not have the motivation or confidence necessary to leave their family of origin. In addition, from a population perspective, there is an advantage to having a group of individuals willing to take more risks and try new methods, counterbalancing the more conservative elements more typical of the received knowledge held by older adults. Risktaking may also have reproductive advantages: adolescents have a newfound priority in sexual attraction and dating, and risk-taking is required to impress potential mates. Research also indicates that baseline sensation seeking may affect risk-taking behavior throughout the lifespan.

Output: Does research favor or reject the hypothesis that adolescents and adults think about risk similarly but hold different values and therefore come to different conclusions?


Input: Consider Input: The land within the borders of current Portugal has been continuously settled and fought over since prehistoric times. The Celts and the Romans were followed by the Visigothic and the Suebi Germanic peoples, who were themselves later invaded by the Moors. These Muslim peoples were eventually expelled during the Christian Reconquista of the peninsula. By 1139, Portugal had established itself as a kingdom independent from León. In the 15th and 16th centuries, as the result of pioneering the Age of Discovery, Portugal expanded Western influence and established the first global empire, becoming one of the world's major economic, political and military powers.
Output: Who were the first inhabitants of Portugal?