TASK DEFINITION: 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.
PROBLEM: Question: Chris is studying two countries. He finds that China has half as many factories putting out fossil fuels into the air than the United States. Based on this information, the factories in _____ are causing more air pollution. 
 Option1: United States 
 Option2: China 
 Explanation: Because richer nations use more fossil fuels, they also cause more air pollution and global warming than poorer nations do.

SOLUTION: United States

PROBLEM: Question: If Jim is screwing in two bolts and the first one has threads that are close together while the second one has threads that are far apart, which one must he apply less force to? 
 Option1: first bolt 
 Option2: second bolt 
 Explanation: The trade-off when the threads are closer together, is that more turns of the screw or bolt are needed to do the job because the distance over which the input force must be applied is greater.

SOLUTION: second bolt

PROBLEM: Question: As waves on the ocean grow in size and number they have. 
 Option1: more energy 
 Option2: less energy 
 Explanation: With higher frequencies, the microwaves also have more energy.

SOLUTION:
more energy