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: Because these isotopes decay more slowly, they can be used to date much older specimens.
 Question: Ron is trying to figure out how old some isotopes are. The isotopes are decaying very slowly, so they are likely specimens that are 
 Choices: A)older 
B)younger
older

Paragraph: More pollutants mean poorer air quality.
 Question: Michael is studying the air quality of various cities. He finds that there are many more pollutants in the air in Mexico City, than there are in the air of Chicago. Therefore, the air quality will be higher in 
 Choices: A)Chicago 
B)Mexico City
Chicago

Paragraph: The more carbon atoms a hydrocarbon has, the greater the number of isomers.
 Question: Compared to a hydrocarbon with 10 carbon atoms, would a hydrocarbon with a single carbon atom have 
 Choices: A)a greater number of isomers 
B)fewer isomers?
fewer isomers?