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.
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Question: 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 50.6days and is used to treat bone cancer due to strontium's chemical similarity and hence ability to replace calcium. While Sr (half-life 28.90years) 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 30,000km 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

Answer: d

Question: Question: Who other than Woldenga has been awarded the Knights cross of the Iron Cross? Passage:Woldenga's career started as a captain in the merchant marine. He started his flight training in 1928 and worked as chief pilot for the FVK Warnemunde. He transferred to the newly emerging Luftwaffe, taking command as Gruppenkommandeur of the I./Jagdgeschwader 131 (JG 131) later renamed to I./Jagdgeschwader 1 (JG 1) on 1 April 1937. With this unit he participated in the invasion of Poland in 1939. He surrender command of the Gruppe on 1 February 1940 and was transferred to the Reichsluftfahrtministerium. He briefly led Jagdgeschwader 27 (JG 27) on the Channel Front from 11 October to 22 October 1940 before he was made Geschwaderkommodore of Jagdgeschwader 77 (JG 77). Under this command, JG 77 participated in the Balkans Campaign and invasion of Crete. JG 77 claimed 50 aerial victories. Woldenga received the Knight's Cross of the Iron Cross. He commanded of JG 27 on 21 June 1941 during the invasion of the Soviet Union and claimed 4 aerial victories. He relocated the Geschwaderstab to North Africa in December 1941. He was appointed Fliegerfuhrer Balkan on 10 June 1942. His last service position of the war was commander of the Luftkriegschule 10 in Furstenwalde near Berlin. He is credited with three aerial victories of which two were claimed on the Eastern Front.
Links: a. Knight's Cross of the Iron Cross b. Furstenwalde c. Furstenwalde d. Jagdgeschwader 77

Answer: a

Question: Question: When was the team that would become the Milwaukee Brewers founded? Passage:In 1977, following years of legal wrangling over the move of the Seattle Pilots to Milwaukee (to become the Milwaukee Brewers), the MLB awarded Seattle a new baseball franchise, the Seattle Mariners. From 1977 the Mariners played in the Kingdome until mid-season 1999 when the team moved across the street to what is now known as T-Mobile Park, where they continue to play today. The WNBA's Seattle Storm arrived in Seattle in 2000, and played at KeyArena through the 2018 season. With KeyArena being closed until at least 2020 for major renovations, the Storm will play for at least the 2019 season at Angel of the Winds Arena in Everett and at Alaska Airlines Arena on the University of Washington campus. In 2013, Seattle's professional women's soccer team Reign FC, including several members of the World Cup winning US women's national team, opened their first season at Starfire Sports Complex and played at Memorial Stadium in Seattle Center through 2018. Starting in the 2019 NWSL season, the Reign began play on their new home pitch at Tacoma's Cheney Stadium.
Links: a. Seattle Pilots b. Seattle Center c. Seattle Pilots d. Women's National Basketball Association

Answer:
a