Using a fixed quantity of resources, a business produces 100 units of good Y and 200 units of good X. It then plans to raise output of good Y to 120 units, and because of this it can produce only 170 units of good X. What is the opportunity cost of making the additional 20 units of good Y?
- A20 units of good X
- B30 units of good X
- C120 units of good X
- D170 units of good X