So starting off with chocolate. 200 people were surveyed. So 100 people would be 0.50 (or half or 50%). So 107 people who prefer chocolate would be a bit more than 0.50. 0.535 prefer chocolate.
Going to vanilla, 93 people prefer it. this is LESS than half so it has to be under 0.50. There is only one that is less than 0.50, which is 0.465. Also using addition, this would be the only logical one.