The statement that best explains the result is: The force of air resistance acts more strongly on the sheet of paper than on the nickel.
In this scenario, while both the nickel and the sheet of paper experience the same gravitational force, the nickel is denser and has a smaller surface area compared to the sheet of paper. This means that the sheet of paper experiences more significant air resistance, which opposes its motion, causing it to fall more slowly than the nickel.