You share a house with two other people. You are a concert pianist and often practice at home. One roommate enjoys listening to you practice, but the other does not. For the roommate who enjoys listening to you play, this is an example of __________; for the other roommate, it is an example of __________. Question 20 options: A) a negative externality; a positive externality B) a negative externality; a negative externality C) a positive externality; a positive externality D) a positive externality; a negative externality