You are given a short paragraph, a question and two choices to answer from. Choose the correct answer based on the paragraph and write the answer(not the key).

Paragraph: Water density increases as salinity and pressure increase, or as temperature decreases.
 Question: By removing a pound of salt from a bucket of fresh water, could you cause the density of the water to 
 Choices: A)increase 
B)decrease?
decrease?

Paragraph: For a given medium such as air, sound has a slower speed at lower temperatures.
 Question: If Mary is blowing an air horn underwater and she raises the temperature of the water, what will happen to the speed of the sound waves generated by the air horn? 
 Choices: A)increase 
B)decrease
increase

Paragraph: Aerobic exercise increases the size and strength of muscles in the heart and helps all your muscles develop greater endurance.
 Question: If Jim works hard and increases the strength of his muscles, his endurance becomes 
 Choices: A)greater 
B)smaller

greater