In this task, you're given a question, a context passage, and four options which are terms from the passage. After reading a passage, you will get a brief understanding of the terms. Your job is to determine by searching and reading further information of which term you can answer the question. Indicate your choice as 'a', 'b', 'c', or 'd'. If you think more than one option is plausible, choose the more probable option to help you answer the question.

Input: Consider Input: Question: In what year was CIA pilot Francis Gary Powers born? Passage:Strategic Air Command was formed by the United States Air Force after World War II to provide an active defense against any surprise attack by the Soviet Union. Though it had been an ally against Germany and Japan during World War II, by 1948 the Soviet Union showed a propensity to instigate problems with Britain, France and the United States. In August 1949, the Soviet Union detonated its first nuclear weapon and by the early 1950s had detonated a hydrogen bomb. The war of words between the two superpowers escalated during 1950s and 1960s into a nuclear arms race. By 1970 the United States was using a "Triad Defense System" composed of nuclear submarines armed with nuclear missiles, land based intercontinental ballistic missiles with nuclear warheads and bombers capable of delivering hydrogen bombs on enemy targets. The Boeing B-52 Stratofortress bomber had been designed in the early 1950s by Boeing Aircraft Company to give the United States Air Force the capability of delivering nuclear weapons far inside the territory of Soviet Russia. The planes were to fly at high altitude with enough fuel to hit their target. In May 1960, the Soviet Union made known its capability to shoot such high altitude planes out of the sky by using a surface to air missile to strike CIA pilot Francis Gary Powers' U-2 spy plane over Russian territory. From that point on, the high-altitude B-52 had to be modified to conduct missions at low level, something it was not intended to be.
 Links: a. Strategic Air Command b. Intercontinental ballistic missile c. Intercontinental ballistic missile d. Francis Gary Powers

Output: d


Input: Consider Input: Question: What city is home to the team that was created for the 2000-01 season? Passage:The 2000–01 season saw the folding of the Summerland Warriors and the creation of the Creston Valley Thunder Cats. In 2001–02, the league was split from two to three divisions, the Neil Murdoch, Eddie Mountain, and Okanagan/Shushwap. Along with the division re-alignment, the North Okanagan Kings relocated to Enderby, becoming the Enderby Ice Kings. The Osoyoos Heat took on the name the Osoyoos Storm, and an expansion franchise was granted to Summerland, which took the name Summerland Sting. 2001–02 also saw the presence of the KIJHL's most accomplished alumnus, Shea Weber, who played for the league champions Sicamous Eagles for this single season. In 2002–03, the Princeton Posse joined the league, becoming the furthest west team in the KIJHL, and the Enderby Ice Kings folded after one season. In 2004–05, the Fernie Ghostriders joined the league from the North American Hockey League, and the following year the Golden Rockets were renamed the Golden Xtreme. They were renamed again the following year, this time becoming the Golden Jets. Also, 2006–07 saw the demise of the Osoyoos Storm, who moved to Kamloops Storm, while retaining the Storm name. In 2007–08, the league was divided into two conferences, which were furthermore split into two divisions each, dropping the Okanagan Shushwap, while creating the Eddie Mountain Conference, East and West Divisions, and likewise with the Neil Murdoch Conference. The Golden Xtreme was again renamed, this time reverting to the Rockets name. Furthermore, the Chase Chiefs joined the league in 2007–08, while the Fernie Ghostriders would capture the league title. There were no team changes in 2008–09, and the Nelson Leafs would capture the league title. In 2009–10, however, the Summerland Sting were forced to relocate to nearby Penticton, taking the name Penticton Lakers. Furthermore, an expansion team was granted to Armstrong, and the North Okanagan Knights were founded.
 Links: a. North American Hockey League b. Creston Valley Thunder Cats c. Summerland Sting d. Penticton Lakers

Output: b


Input: Consider Input: Question: Who are the members of the group that helped John Baldwin with infrared imaging? Passage:In the 1970s, astronomers saw some major advances in astronomical imaging technology, beginning with Antoine Labeyrie's invention of speckle interferometry, a process that significantly reduced the blurring effect caused by astronomical seeing. It increased the optical resolution of ground-based telescopes, allowing for more precise measurements of Betelgeuse's photosphere. With improvements in infrared telescopy atop Mount Wilson, Mount Locke and Mauna Kea in Hawaii, astrophysicists began peering into the complex circumstellar shells surrounding the supergiant, causing them to suspect the presence of huge gas bubbles resulting from convection. But it was not until the late 1980s and early 1990s, when Betelgeuse became a regular target for aperture masking interferometry, that breakthroughs occurred in visible-light and infrared imaging. Pioneered by John E. Baldwin and colleagues of the Cavendish Astrophysics Group, the new technique employed a small mask with several holes in the telescope pupil plane, converting the aperture into an ad-hoc interferometric array. The technique contributed some of the most accurate measurements of Betelgeuse while revealing bright spots on the star's photosphere. These were the first optical and infrared images of a stellar disk other than the Sun, taken first from ground-based interferometers and later from higher-resolution observations of the COAST telescope. The "bright patches" or "hotspots" observed with these instruments appeared to corroborate a theory put forth by Schwarzschild decades earlier of massive convection cells dominating the stellar surface.
 Links: a. Cavendish Astrophysics Group b. Aperture masking interferometry c. Aperture masking interferometry d. Mount Wilson Observatory


Output: a