Which of the following would be classified as an external cost?
◦ As more firms began hiring computer programmers, the salaries of computer programmers increased, and therefore the firm's cost of production increased.
◦ A private firm will not provide national defense, as it is impossible to confine the benefits to only those individuals who have paid for it.
◦ You are not able to study at night because there is so much noise coming from the dorm room next to yours.
◦ When you purchase a prescription drug, you are not made fully aware of all the possible side effects that may result from taking the drug.