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: In 121 BC, Han forces expelled the Xiongnu from a vast territory spanning the Hexi Corridor to Lop Nur. They repelled a joint Xiongnu-Qiang invasion of this northwestern territory in 111 BC. In that year, the Han court established four new frontier commanderies in this region: Jiuquan, Zhangyi, Dunhuang, and Wuwei. The majority of people on the frontier were soldiers. On occasion, the court forcibly moved peasant farmers to new frontier settlements, along with government-owned slaves and convicts who performed hard labor. The court also encouraged commoners, such as farmers, merchants, landowners, and hired laborers, to voluntarily migrate to the frontier.

Answer: Who made up a majority of the people on the frontier?

Question: Desktop computers and laptops are commonly infected with malware either to gather passwords or financial account information, or to construct a botnet to attack another target. Smart phones, tablet computers, smart watches, and other mobile devices such as Quantified Self devices like activity trackers have also become targets and many of these have sensors such as cameras, microphones, GPS receivers, compasses, and accelerometers which could be exploited, and may collect personal information, including sensitive health information. Wifi, Bluetooth, and cell phone network on any of these devices could be used as attack vectors, and sensors might be remotely activated after a successful breach.

Answer: What are desktop computers and laptops commonly infected with?

Question: Conflict between the Germanic tribes and the forces of Rome under Julius Caesar forced major Germanic tribes to retreat to the east bank of the Rhine. Roman emperor Augustus in 12 BC ordered the conquest of the Germans, but the catastrophic Roman defeat at the Battle of the Teutoburg Forest resulted in the Roman Empire abandoning its plans to completely conquer Germany. Germanic peoples in Roman territory were culturally Romanized, and although much of Germany remained free of direct Roman rule, Rome deeply influenced the development of German society, especially the adoption of Christianity by the Germans who obtained it from the Romans. In Roman-held territories with Germanic populations, the Germanic and Roman peoples intermarried, and Roman, Germanic, and Christian traditions intermingled. The adoption of Christianity would later become a major influence in the development of a common German identity.

Answer:
What emperor forced the Germanic tribes to the east side of the Rhine?