I hope this help
Select one serving is the healthiest choice here, because by taking only one serving you won't eat to much calories from the chips, and also you won't reject your friend's offering which isn't a good habit. Also, other options just adds more calories by eating a lot, like "eat until you are satisfied" or "split in half", that represents too much chips, which is not healthy.
the gravitational force on an object increase as the mass of an object also, im not going to report you, but this question should be under the science category, not health
i agree d is most definitely correct!