Which of the following statements from “Roller Coaster Physics” BEST explains gravity’s effect on a person riding a roller coaster? A Once the train cars crest the lift hill, gravity pulls the front of the train down the tracks. B Gravity is channeled through the train tracks. C Once down the lift hill, the next hill causes gravity to place a downward force on the back of the train, causing deceleration. D As the train climbs another hill and experiences deceleration, the body no longer feels the push of gravity, but the next ride down a hill brings back the sensation.