In this task, you need to provide the correct option for a given problem from the provided options.
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Question: Problem: if 1 = 3 2 = 6 3 = 9 4 = 12 5 = 15 then 9 = ? hint : its a logic riddle not a mathematical riddle 
Options: a ) 1 , b ) 2 , c ) 3 , d ) 4 , e ) 5

Answer: c


Question: Problem: if x and y are both odd prime numbers and x < y , how many distinct positive integer factors does 2 xy have ? 
Options: a ) 3 , b ) 4 , c ) 6 , d ) 8 , e ) 12

Answer: d


Question: Problem: a certain university will select 1 of 7 candidates eligible to fill a position in the mathematics department and 2 of 8 candidates eligible to fill 2 identical positions in the computer science department . if none of the candidates is eligible for a position in both departments , how many different sets of 3 candidates are there to fill the 3 positions ? 
Options: a ) 42 , b ) 70 , c ) 140 , d ) 196 , e ) 315

Answer:
d