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).

[EX Q]: Paragraph: In the mesosphere, temperature decreases as altitude increases.
 Question: When we get higher in the air what happens to the temperature? 
 Choices: A)goes up 
B)goes down
[EX A]: goes down

[EX Q]: Paragraph: The closer together the particles are, the greater the amplitude of the wave.
 Question: A wave's amplitude will be _____ the closer its particles become. 
 Choices: A)higher 
B)lower
[EX A]: higher

[EX Q]: Paragraph: At higher concentrations, particles of reactants are crowded closer together, so they are more likely to collide and react.
 Question: Ian sees an object with few colliding particles, and he compares it to another object with few colliding particles. Which is true about the objects? 
 Choices: A)the object with many colliding particles has a lower concentration of particles 
B)the object with many colliding particles has a higher concentration of particles
[EX A]:
the object with many colliding particles has a lower concentration of particles