In this task, you need to provide the correct option for a given problem from the provided options.

Q: Problem: in a bag , there are 2400 ball , and their colors are red , green blue . . the ratio of the balls are 15 : 13 : 17 . then how many red color balls are available in the bag ? 
Options: a ) 900 , b ) 1600 , c ) 750 , d ) 890 , e ) 1010

A: a
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Q: Problem: there are 8 executives , including the ceo and cfo , that are asked to form a small team of 4 members . however , the ceo and cfo may not both be assigned to the team . given this constraint , how many ways are there to form the team ? 
Options: a ) 45 , b ) 55 , c ) 65 , d ) 75 , e ) 85

A: b
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Q: Problem: if a and b are both odd prime numbers and a < b , then how many different positive integer factors does 2 ab have ? 
Options: a ) 3 , b ) 4 , c ) 6 , d ) 8 , e ) 12

A:
d
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