Which of the Following Statements Is True

Which of the following statements is true?

A) If a buyer ends up being worse off from an exchange rather than better off as expected, this is a negative externality.
B) Secondhand cigarette smoke is an example of a negative externality.
C) As long as the benefits to society from an exchange outweigh the costs to society, no negative externality has occurred.
D) As long as the benefits to society from an exchange outweigh the costs to the producer of the good or service, no negative externality has occurred.