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: When the heart expels more blood with each stroke, the heart has to beat less often in order to maintain the same volume of blood flow.
 Question: Jon was jogging, and quickening his pace. His heart is beating _____. 
 Choices: A)more 
B)less
more

Paragraph: Increasing the number of resistors in a series circuit increases the overall resistance of the circuit.
 Question: Greta has 15 resistors in series on her circuit, while Evan has 2 similar resistors in series on his circuit. Whose circuit has the greatest resistance? 
 Choices: A)Greta 
B)Evan
Greta

Paragraph: Solar power is expensive, but as demand increases technology improves and costs decrease.
 Question: Years from now, solar power will be _____ than it is today. 
 Choices: A)more expensive 
B)less expensive

less expensive