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: How old was Nusslein-Volhard when she won the Nobel Prize in Physiology and Medicine? Passage:The concept of the morphogen has a long history in developmental biology, dating back to the work of the pioneering Drosophila (fruit fly) geneticist, Thomas Hunt Morgan, in the early 20th century. Lewis Wolpert refined the morphogen concept in the 1960s with the French flag model, which described how a morphogen could subdivide a tissue into domains of different target gene expression (corresponding to the colours of the French flag). This model was championed by the leading Drosophila biologist, Peter Lawrence. Christiane Nusslein-Volhard was the first to identify a morphogen, Bicoid, one of the transcription factors present in a gradient in the Drosophila syncitial embryo. She was awarded the 1995 Nobel Prize in Physiology and Medicine for her work explaining the morphogenic embryology of the common fruit fly. Groups led by Gary Struhl and Stephen Cohen then demonstrated that a secreted signalling protein, Decapentaplegic (the Drosophila homologue of transforming growth factor beta), acted as a morphogen during the later stages of Drosophila development.
 Links: a. Christiane Nüsslein-Volhard b. Lewis Wolpert c. Lewis Wolpert d. Transcription factor

Output: a


Input: Consider Input: Question: How old was the king when he awarded Mairi and Knocker the Order of Léopold II, Knights Cross? Passage:Chisholm and Knocker soon came to the conclusion that they could save more lives by treating the wounded directly on the front lines. In November, they decided to leave the corps and set up their own dressing station five miles east in a town named Pervyse, north of Ypres, just one hundred yards from the trenches. Here, in a vacant cellar which they named "Poste de Secours Anglais" ("British First Aid Post"), the two would spend the next three and a half years tending to the wounded. No longer affiliated with the Belgian Red Cross, they began acting completely as free agents and had to support their work by raising their own funds. Through sheer perseverance Knocker was able to arrange for the two of them to be officially seconded to the Belgian garrison stationed there. In January 1915, they were both decorated by King Albert I of Belgium with the Order of Léopold II, Knights Cross (with palm) for their courageous work on the front lines. They were also awarded the British Military Medal and both made Officers of the Most Venerable Order of St. John of Jerusalem. Chisholm was also decorated with the Queen Elisabeth Medal of Belgium and the British campaign medals, including the 1914 Star. The two became instant celebrities earning the distinction of being among the most photographed women of the war.
 Links: a. Ypres b. Albert I of Belgium c. Queen Elisabeth Medal d. Pervijze

Output: b


Input: Consider Input: Question: How far away from the town of his birth was the academy that Morison attended at age 14? Passage:Born in New Bedford, Massachusetts, he was the son of John Hopkins Morison, a Unitarian minister. At age 14, he entered Phillips Exeter Academy and graduated by age 16. He went on to Harvard College where he was a classmate of philosopher John Fiske. Morison received a Bachelor of Arts degree in 1863 when he was just 20. After a brief break he attended Harvard Law School where he would receive a Bachelor of Laws degree by 1866 and was admitted to the New York Bar. In 1867, with only general mathematics training and an aptitude for mechanics, he abandoned the practice of law and pursued a career as a civil engineer and builder of bridges. He would apprentice under the supervision of engineer Octave Chanute during the construction of the first bridge to cross the Missouri River, the swing-span Kansas City Bridge.
 Links: a. New Bedford, Massachusetts b. John Fiske (philosopher) c. Mathematics d. Harvard College


Output: a