The word "less" belongs in the blank.
You're letting Physics scare you so stiff that you're afraid to even think about it. But right now, I'm asking you to do just that . . . turn your brain on and THINK about this question for about 3 seconds:
Here's what the question is asking:
If you push on a ping-pong ball and a school-bus with the same strength of force, which one will move away from you faster ?