You are given a mathematical question described with an open-ended vocabulary. Questions in this task involve real-world situations, describing a mathematical problem. You are also given 4 or 5 answer options (associated with "A", "B", "C", "D", "E"). Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D', 'E'. LaTeX mathematical format (the standard way to express mathematical expressions in the typesetting software known as LaTeX) is used to express equations. Each question is solvable with high school math knowledge. Give only one answer for each question.
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Question: In an airport security line, every 20th person has his bag searched, and every 10th person is asked to put her shoes through a special X-ray machine. Of 100 passengers, what is the probability that a passenger will be asked to put his shoes through the X-ray and have his bag searched?
(A)\(\frac{1}{100}\) (B)\(\frac{1}{50}\) (C)\(\frac{1}{20}\) (D)\(\frac{1}{10}\) (E)\(\frac{1}{5}\)

Answer: C


Question: If Anthony had 3 times as many marbles as he actually has, he would have 5 as many marbles as Billy has. What is the ratio of the number of marbles Anthony has to the number of marbles Billy has?
(A)1 : 9 (B)1 : 3 (C)1 : 1 (D)3 : 1 (E)9 : 1

Answer: A


Question: A school's honor society has 100 members: 40 boys and 60 girls, of whom 30 are juniors and 70 are seniors. What is the smallest possible number of senior boys in the society?
(A)0 (B)5 (C)10 (D)15 (E)20

Answer:
C