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).

Let me give you an example: Paragraph: Many of the worlds people live with water scarcity, and that percentage will increase as populations increase and climate changes.
 Question: John's town used to have lots of water, back when there were only a few hundred people. However, now that the town holds several thousand people, the water availability is 
 Choices: A)scarce 
B)plentiful
The answer to this example can be: scarce
Here is why: Based on the information given in the paragraph, population growth will make water more scarce, so that is the correct answer.

OK. solve this:
Paragraph: Smoking reduces the amount of oxygen available for diffusion at the lungs, so less oxygen gets absorbed and blood is oxygenated to a lesser degree.
 Question: Suppose that Mary smokes cigarettes for 20 years. If you measured the oxygen levels in her blood before she started smoking and compared them to oxygen levels later in her life, what would you find? 
 Choices: A)less oxygen in her blood later in life 
B)more oxygen in her blood later in life
Answer:
less oxygen in her blood later in life