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There are x red marbles, y blue marbles, and z yellow marbles in a sack. Three marbles are chosen at random, without replacements. If x, y, and z are all at least equal to 3, then which of the following must be true? Indicate all possible values.
A.The probability of drawing exactly 3 red marbles is(x/(x+y+z))((x−1)/(x+y+z−1))((x−2)/(x+y+z−2))
B.The probability of drawing at least 1 red marble is1−((y+z)/(x+y+z))((y+z−1)/(x+y+z−1))((y+z−2)/(x+y+z−2))
C.The probability of drawing exactly 3 blue marbles is(y/(x+y+z))((y−z)/(x+y+z−1))((y+z)/(x+y+z−2))
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