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: For example, more people on the Earth means more people contributing to global warming and pollution.
 Question: What will happen to the levels of pollution on Earth if the population decreases? 
 Choices: A)they will rise 
B)they will fall
they will fall

Paragraph: As more resistors are added in series, the total resistance of the circuit increases.
 Question: If Ed adds a resistor to the circuit, the resistance will be 
 Choices: A)greater 
B)lower.
greater

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: Will is smoking a cigarette. This causes _____ oxygen to be available for diffusion in his lungs, so less oxygen will be absorbed into his blood. 
 Choices: A)more 
B)less
less