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.

Q: 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.

A: United States
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Q: Question: If Jim is an endotherm would his body give off _____ heat if the blood flow to the surface of his body were decreased? 
 Option1: more 
 Option2: less 
 Explanation: On a hot day, an endotherm may give off more heat by increasing blood flow to the surface of the body.

A: less
****
Q: Question: Dave dropped a feather and a ball out of a window. The ball landed last because it had mass that, compared to the feather, was 
 Option1: greater 
 Option2: lesser 
 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.

A:
lesser
****