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.

Q: Question: How many people died in the incident that contaminated about 30,000 km?  Passage:Natural strontium is a mixture of four stable isotopes: Sr, Sr, Sr, and Sr. Their abundance increases with increasing mass number and the heaviest, Sr, makes up about 82.6% of all natural strontium, though the abundance varies due to the production of radiogenic Sr as the daughter of long-lived beta-decaying Rb. Of the unstable isotopes, the primary decay mode of the isotopes lighter than Sr is electron capture or positron emission to isotopes of rubidium, and that of the isotopes heavier than Sr is electron emission to isotopes of yttrium. Of special note are Sr and Sr. The former has a half-life of 50.6 days and is used to treat bone cancer due to strontium's chemical similarity and hence ability to replace calcium. While Sr (half-life 28.90 years) has been used similarly, it is also an isotope of concern in fallout from nuclear weapons and nuclear accidents due to its production as a fission product. Its presence in bones can cause bone cancer, cancer of nearby tissues, and leukemia. The 1986 Chernobyl nuclear accident contaminated about 30,000 km with greater than 10 kBq/m with Sr, which accounts for 5% of the core inventory of Sr.
 Links: a. Rubidium b. Mass number c. Electron capture d. Chernobyl disaster

A: d
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Q: Question: What was the score in Mannarino's loss in straight sets? Passage:The unseeded Mannarino reached his third career ATP World Tour singles final at the 2017 Antalya Open; he defeated two seeded players Borna Ćorić (in the first round) and Fernando Verdasco (in the quarterfinals) to advance to the final, where he lost to Yūichi Sugita in straight sets. At the Wimbledon Championships one week later, Mannarino upset no. 19 seed Feliciano López in the first round and no. 15 seed Gaël Monfils in the third round before losing to no. 2 seed Novak Djokovic in the fourth round. He reached his first career ATP World Tour Masters 1000 singles quarterfinal at the 2017 Rogers Cup, where he upset no. 6 seed and world no. 10 Milos Raonic in the second round before losing to Denis Shapovalov in the quarterfinals. The unseeded Mannarino defeated top seed and world no. 5 Marin Čilić (the biggest singles win of his career and his first career win over a member of the Top 5 in the ATP singles rankings) in the semifinals of the Japan Open to reach his first career ATP World Tour 500 Series singles final, where he lost to fourth-seeded David Goffin. In October, Mannarino reached his third ATP World Tour singles semi-final of 2017 at the Kremlin Cup, where he lost to Ričardas Berankis. The following week, the 7th seeded Mannarino lost in the quarterfinals of the Swiss Indoors to top seed Roger Federer in three sets.
 Links: a. Denis Shapovalov b. 2017 Antalya Open – Singles c. Denis Shapovalov d. Marin Čilić

A: b
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Q: Question: On what date was the treaty signed that transferred the land that would become Wisconsin the the U.S.? Passage:The U.S. state of Wisconsin is divided into 72 counties. The land that eventually became Wisconsin was transferred from British to American control with the 1783 signing of the Treaty of Paris. It was an unorganized part of the Northwest Territory until 1802 when all of the land from St. Louis north to the Canadian border was organized as St. Clair County. When Illinois was admitted to the union in 1818, Wisconsin became part of the Territory of Michigan and divided into two counties: Brown County in the northeast along Lake Michigan and Crawford County in the southwest along the Mississippi River. Iowa County was formed in 1829 from the Crawford County land south of the Wisconsin River. Brown County's southern portion was used to form Milwaukee County in 1834. The state of Wisconsin was created from Wisconsin Territory on May 29, 1848, with 28 counties.
 Links: a. County (United States) b. Treaty of Paris (1783) c. Crawford County, Wisconsin d. Wisconsin

A:
b
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