In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

[EX Q]: Factories in China often produce what type of gas in their emissions that acts as pollution?, Context: A dense wave of smog began in the Central and Eastern part of China on 2 December 2013 across a distance of around 1,200 kilometres (750 mi), including Tianjin, Hebei, Shandong, Jiangsu, Anhui, Shanghai and Zhejiang. A lack of cold air flow, combined with slow-moving air masses carrying industrial emissions, collected airborne pollutants to form a thick layer of smog over the region. The heavy smog heavily polluted central and southern Jiangsu Province, especially in and around Nanjing, with its AQI pollution Index at "severely polluted" for five straight days and "heavily polluted" for nine. On 3 December 2013, levels of PM2.5 particulate matter average over 943 micrograms per cubic metre, falling to over 338 micrograms per cubic metre on 4 December 2013. Between 3:00 pm, 3 December and 2:00pm, 4 December local time, several expressways from Nanjing to other Jiangsu cities were closed, stranding dozens of passenger buses in Zhongyangmen bus station. From 5 to 6 December, Nanjing issued a red alert for air pollution and closed down all kindergarten through middle schools. Children's Hospital outpatient services increased by 33 percent; general incidence of bronchitis, pneumonia, upper respiratory tract infections significantly increased. The smog dissipated 12 December. Officials blamed the dense pollution on lack of wind, automobile exhaust emissions under low air pressure, and coal-powered district heating system in North China region. Prevailing winds blew low-hanging air masses of factory emissions (mostly SO2) towards China's east coast.
[EX A]: SO2

[EX Q]: Who were the communists that came to power?, Context: Following the breakup of the Russian Empire in the aftermath of World War I for a brief period, from 1918 to 1920, Armenia was an independent republic. In late 1920, the communists came to power following an invasion of Armenia by the Red Army, and in 1922, Armenia became part of the Transcaucasian SFSR of the Soviet Union, later forming the Armenian Soviet Socialist Republic (1936 to September 21, 1991). In 1991, Armenia declared independence from the USSR and established the second Republic of Armenia.
[EX A]: Transcaucasian SFSR of the Soviet Union

[EX Q]: What is the main thing that the director does?, Context: The FBI director is responsible for the day-to-day operations at the FBI. Along with his deputies, the director makes sure cases and operations are handled correctly. The director also is in charge of making sure the leadership in any one of the FBI field offices is manned with qualified agents. Before the Intelligence Reform and Terrorism Prevention Act was passed in the wake of the September 11 attacks, the FBI director would directly brief the President of the United States on any issues that arise from within the FBI. Since then, the director now reports to the Director of National Intelligence (DNI), who in turn reports to the President.
[EX A]:
day-to-day operations