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).

[Q]: Paragraph: If there are more greenhouse gases in the atmosphere, more ultraviolet radiation will be trapped and the Earth will heat up.
 Question: Carl is studying climate change, and notes that less ultraviolet radiation is being trapped, which means the earth will be 
 Choices: A)cooler 
B)warmer
[A]: cooler


[Q]: Paragraph: The more tightly packed the particles inside the material are, the more dense we say they are.
 Question: Sasha is throwing bottles into the lake. Some bottles are filled with sand, and some only have a tiny bit of sand in them. The bottles with a tiny bit of sand will sink last because they are 
 Choices: A)less dense 
B)more dense
[A]: less dense


[Q]: Paragraph: The more dense the medium, the slower the light moves.
 Question: A very dense medium will cause light to move 
 Choices: A)faster 
B)slower
[A]:
slower