instruction:
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.
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 50.6 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
answer:
d


question:
Question: When did Frank Damrosch's school change names? Passage:Willson was born in Mason City, Iowa to John David Willson and Rosalie Reiniger Willson. He had a brother two years his senior, John Cedrick, and a sister twelve years his senior, the children's author Dixie Willson. Willson attended Frank Damrosch's Institute of Musical Art (which later became the Juilliard School) in New York City. He married his high school sweetheart, Elizabeth "Peggy" Wilson, on August 29, 1920. Willson, a flute and piccolo player, was a member of John Philip Sousa's band (1921–1923), and later the New York Philharmonic Orchestra under Arturo Toscanini (1924–1929). Willson then moved to San Francisco, California as the concert director for radio station KFRC, and then as a musical director for the NBC radio network in Hollywood. His on-air radio debut came on KFRC in 1928 on Blue Monday Jamboree.
 Links: a. Frank Damrosch b. Mason City, Iowa c. Juilliard School d. John Philip Sousa
answer:
c


question:
Question: How many casualties were there at the battle Dearing fought at under Jubal Early? Passage:Dearing traveled to Richmond, Virginia, getting a commission as lieutenant of artillery in the Virginia Militia. He joined the recently arrived Washington Artillery from New Orleans, Louisiana; and was commissioned as 2nd Lieutenant and drill instructor in the 3rd company. He participated in the First Battle of Bull Run while being assigned to the 1st company as part of the 4th Brigade of Colonel Jubal Early in the Army of the Potomac, and served as volunteer aide to his battalion commander Major James B. Walton. Dearing was promoted to 1st Lieutenant in July 1861; and to Captain in April 1862 when he became commander of the reorganized Lynchburg ("Latham´s") Battery. Dearing's (Virginia) Battery was attached to George E. Pickett's Brigade and supported it in the Peninsular Campaign, where Dearing was highly praised by Lieutenant General James Longstreet, and in the Second Battle of Bull Run. When Pickett was elevated to division command in Longstreet's First Corps in September Dearing's battery was assigned to the division and fought in the Battle of Fredericksburg.
 Links: a. James B. Walton b. Richmond, Virginia c. First Battle of Bull Run d. Battle of Fredericksburg
answer:

c