You are given a question or fill-in-the-blank question, two answer options (Option1 and Option2) and an Explanation. Your task is to find the correct answer (return the string of the correct option, not option1/2) for the given question from the given options and using explanation.

Question: A rock has more mass than a pebble. Which object will exhibit a smaller force of attraction? 
 Option1: rock 
 Option2: pebble 
 Explanation: The greater the objects mass, the greater the force of attraction; in addition, the greater the distance between objects, the smaller the force of attraction.
pebble

Question: A wave with a shorter wavelength will have a _____ frequency 
 Option1: longer 
 Option2: shorter 
 Explanation: Because all electromagnetic waves travel at the same speed through space, a wave with a shorter wavelength must have a higher frequency, and vice versa.
longer

Question: If Jim is playing with some objects and moving them around and he moves them farther apart, the gravitational force between them 
 Option1: increases 
 Option2: decreases 
 Explanation: The closer objects are to each other, the stronger the gravitational force between them.

decreases