Which of the following is a correct statement about pro...
单项选择题Which of the following is a correct statement about production possibilities frontiers?
A．An economy can produce at any point inside the production possibilities frontier, but not on or outside the frontier.
B．An economy can produce at any point on or inside the production possibilities frontier, but not outside the frontier.
C．An economy can produce only on the production possibilities frontier.
D．An economy can produce at any point inside or outside a production possibilities frontier.
