Correct Answer: Option D
Here, Number of red ball =3 white ball=4 blue ball=5 suppose, one picked five balls there is a possiblity that all of them are blue balls. then again,if one picked another 4 balls (total 9) then there is a possiblity that all of them are Blue and White.
After that if one picked only one ball, then 10th ball must will be red. so,total balls he must pick=5+4+1 =10
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