Hi I think the answer would be B If you add up all the numbers it equals 50 and then add football and tennis together that equals 13, and then you have to divide 13/50 which equals 0.26 (26%)
Talking as if the balls do not get put back into the bag, the first probability is 3/10 for yellow. For red it will be 7/9 because there is one less ball (yellow) in the bag.