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.
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Question: Question: If Mona is bouncing radar waves off a test car when training to be a policewoman and she notices the frequency of the waves returning to her radar gun is lower then it was before, what is happening to the car she is pointing the gun at? 
 Option1: decreasing in speed 
 Option2: increasing in speed 
 Explanation: A: As the car approaches the radar gun, the reflected microwaves get bunched up in front of the car. Therefore, the waves the receiver detects have a higher frequency than they would if they were being reflected from a stationary object. The faster the car is moving, the greater the increase in the frequency of the waves.

Answer: decreasing in speed


Question: Question: As we turn down the volume on a stereo that we are listening to the sound waves get 
 Option1: smaller 
 Option2: larger 
 Explanation: As decibel levels get higher, sound waves have greater intensity and sounds are louder.

Answer: smaller


Question: Question: What would happen to the amount of carbon dioxide emitted if the amount of fossil fuels were increased? 
 Option1: increase 
 Option2: decrease 
 Explanation: The carbon taxes encourage people to use less fossil fuel, which reduces carbon dioxide emissions.

Answer:
increase