In this task, you will be presented with a context passage, a question about that paragraph, and a possible answer to that question. The task is to check the validity of the answer. Answer with "Yes" or "No".

Ex Input:
The inhabited history of the Las Vegas Valley stretches to 23,000 b.c. , when much of the area was covered by a prehistoric lake. During this period, the indigenous people lived in caves, hunting the mammals that gathered at the shoreline. The landscape of the valley changed dramatically over the next 200 centuries. The glaciers feeding the lake melted away and the lake evaporated. Fossils tell an obscure story of man's slow and sporadic development. Around 3000 b.c. , native Archaic Indians began to develop a lasting hunting and gathering culture. By this time, the valley was in much the same geographic state as it exists in today, with one exceptionthe presence of artesian springs that bubbled to the surface in several areas. These springs fed a network of streams draining through the Las Vegas Wash to the Colorado River. The areas surrounding the springs were desert oases: sprawling collections of grasses, trees, and wildlife. Many springs lay in areas that would eventually become the center of the modern Las Vegas metropolis. For about 4000 years, the Archaics thrived in a culture that included many signs of early civilization. Signs of even more advancement appeared halfway through the first millennium a.d. , when the Anasazi Indians inhabited the valley. Far more progressive than the Archaics, the Anasazi utilized such formal agricultural techniques as irrigation to assist their harvest. This permitted the Anasazi to achieve a benchmark of advanced societythe ability to live in permanent shelters year-round without need to follow wildlife. Mysteriously, the Anasazi vanished from the valley around a.d. <sep>Why did the prehistoric lake disappear from the Las Vegas Valley?<sep>Deforestation

Ex Output:
No

Ex Input:
In short, the United States has to help defeat an ideology, not just a group of people, and we must do so under difficult circumstances. How can the United States and its friends help moderate Muslims combat the extremist ideas? Recommendation: The U.S. government must define what the message is, what it stands for. We should offer an example of moral leadership in the world, committed to treat people humanely, abide by the rule of law, and be generous and caring to our neighbors. America and Muslim friends can agree on respect for human dignity and opportunity. To Muslim parents, terrorists like Bin Laden have nothing to offer their children but visions of violence and death. America and its friends have a crucial advantage-we can offer these parents a vision that might give their children a better future. If we heed the views of thoughtful leaders in the Arab and Muslim world, a moderate consensus can be found. That vision of the future should stress life over death: individual educational and economic opportunity. This vision includes widespread political participation and contempt for indiscriminate violence. It includes respect for the rule of law, openness in discussing differences, and tolerance for opposing points of view. Recommendation: Where Muslim governments, even those who are friends, do not respect these principles, the United States must stand for a better future. One of the lessons of the long Cold War was that short-term gains in cooperating with the most repressive and brutal governments were too often outweighed by long-term setbacks for America's stature and interests. American foreign policy is part of the message. America's policy choices have consequences. Right or wrong, it is simply a fact that American policy regarding the Israeli-Palestinian conflict and American actions in Iraq are dominant staples of popular commentary across the Arab and Muslim world. That does not mean U.S. choices have been wrong. It means those choices must be integrated with America's message of opportunity to the Arab and Muslim world. <sep>Which parents can be offered a vision that might give their children a better future?<sep>Arab parents

Ex Output:
No

Ex Input:
After the 1998 embassy bombings, the U.S. government tried to develop a clearer picture of Bin Laden's finances. A U.S. interagency group traveled to Saudi Arabia twice, in 1999 and 2000, to get information from the Saudis about their understanding of those finances. The group eventually concluded that the oft-repeated assertion that Bin Laden was funding al Qaeda from his personal fortune was in fact not true. The officials developed a new theory: al Qaeda was getting its money elsewhere, and the United States needed to focus on other sources of funding, such as charities, wealthy donors, and financial facilitators. Ultimately, although the intelligence community devoted more resources to the issue and produced somewhat more intelligence, it remained difficult to distinguish al Qaeda's financial transactions among the vast sums moving in the international financial system. The CIA was not able to find or disrupt al Qaeda's money flows. The NSC staff thought that one possible solution to these weaknesses in the intelligence community was to create an all-source terrorist-financing intelligence analysis center. Clarke pushed for the funding of such a center at Treasury, but neither Treasury nor the CIA was willing to commit the resources. Within the United States, various FBI field offices gathered intelligence on organizations suspected of raising funds for al Qaeda or other terrorist groups. By 9/11, FBI agents understood that there were extremist organizations operating within the United States supporting a global jihadist movement and with substantial connections to al Qaeda. The FBI operated a web of informants, conducted electronic surveillance, and had opened significant investigations in a number of field offices, including New York, Chicago, Detroit, San Diego, and Minneapolis. On a national level, however, the FBI never used the information to gain a systematic or strategic understanding of the nature and extent of al Qaeda fundraising. Treasury regulators, as well as U.S. financial institutions, were generally focused on finding and deterring or disrupting the vast flows of U.S. currency generated by drug trafficking and high-level international fraud. Large-scale scandals, such as the use of the Bank of New York by Russian money launderers to move millions of dollars out of Russia, captured the attention of the Department of the Treasury and of Congress. Before 9/11, Treasury did not consider terrorist financing important enough to mention in its national strategy for money laundering. <sep>Where were field offices opened to investigate al Qaeda funding?<sep>Chicago

Ex Output:
Yes