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

Q: Problem: a certain university will select 1 of 7 candidates eligible to fill a position in the mathematics department and 3 of 10 candidates eligible to fill 3 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 4 candidates are there to fill the 4 positions ? 
Options: a ) 420 , b ) 770 , c ) 840 , d ) 165 , e ) 315

A: c
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Q: Problem: if q and d are both integers , q > d , and - 3 q > 19 , then the largest value of d would be ? 
Options: a ) - 5 , b ) - 6 , c ) - 7 , d ) - 8 , e ) - 10

A: d
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Q: Problem: the marks obtained by polly and sandy are in the ratio 4 : 5 and those obtained by sandy and willy are in the ratio of 5 : 2 . the marks obtained by polly and willy are in the ratio of . . . ? 
Options: a ) 2 : 1 , b ) 3 : 2 , c ) 4 : 3 , d ) 5 : 4 , e ) 6 : 5

A:
a
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