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".

Example Input: The Golden Heian Era: The geomancers in 794 decided that Heian-kyo (modern Kyoto) would be an auspicious site for the imperial family. It was indeeduntil 1869. Grants of tax-free land over the years had been made to Buddhist temples and members of the court aristocracy. The most powerful families thus carved out for themselves whole regions that were to become the fiefdoms of Japanese feudalism. By the end of the eighth century the clans had created a hierarchy of shiki, or rights, from the highest to the lowest ranks of society. The aristocrat or court patron lent his prestige to a powerful provincial proprietor, who employed a competent estate-manager to oversee smallholders, who in turn worked their farms with dependent laborers. This elaborate structure of interdependent rights and obligations was to serve Japanese society right into the 20th century. Meanwhile, Heian court life blossomed in an effusion of aesthetic expression. Princes and princesses judged the merits of birds, insects, flowers, roots, or seashells. Literary party games held in ornate palace gardens required each guest to compose a small poem as his wine cup floated toward him along a miniature winding channel of water. Expeditions were organized to the best viewing points for the first spring cherry blossoms, and special pavilions were built to watch the rising of the full moon. Every gesture, from the most banal opening of an umbrella to the sublimest act of lovemaking, had its appropriate ceremonial. Conversation often took the form of elegant exchanges of improvised verse. The changing role of Chinese culture in Japanese life was epitomized in the language itself. In the absence of an indigenous alphabet, Japanese scholars had with the greatest difficulty tried to adapt the complex ideograms of monosyllabic Chinese to the essentially polysyllabic Japanese. Thus developed the katakana system used as a vehicle for writing Buddhist names and concepts. After rival Fujiwara factions had been struggling for years to gain control of the imperial throne, they turned to the Taira and Minamoto armies in 1156 to wage the four-year war that heralded the end of the golden age of the Heian court. The Taira, controlling the region along the Inland Sea, defeated the Minamoto armies based in the Kanto province east of the capital. <sep>Who invaded Kyoto and what was the outcome?<sep>Japanese scholars
Example Output: No

Example 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
Example Output: No

Example Input: A stranger in town meets pretty young Susan Martinez De La Cruz and accompanies her to a barbecue , where wealthy Jason Carberry is saying a few words for the recently departed Robin Randall , a citizen who got shot . Jason objects to the stranger's presence , being Susan's guardian and protective of her . He challenges him to a shootout , but the stranger pulls his pistol before Jason's can even clear the holster . Calaveras Kate , a saloon singer who's in love with Jason , is relieved when the stranger declines to pull the trigger . Rafael Moreno suddenly rides into town and picks a fight with the stranger . Their brawl continues until the arrival of Judge Wallace Wintrop and his niece , Sheila , who have come to town from back East and deplore all this random violence out West . The stranger is recognized as Reb Randall , the dead man's brother . He is looking for the killer , who could be Rafael , or could be Jason , or could even be Billy Buckett , the coward of the county . The women hold their breath to see if the men they love will survive . <sep>Who wants to look for the killer?<sep>Reb Randall
Example Output:
Yes