PPC Shape Indicates Opportunity Cost Type

Steps:

• Recall that a production possibility curve (PPC) graphs trade-offs between two goods.
• Constant opportunity cost means the slope (ratio of goods forgone) stays the same, producing a straight-line PPC.
• Increasing opportunity cost results in a bowed-out (concave) PPC as resources specialize.
• Examine each diagram's shape to match against these patterns.

Why A is correct:

• A straight-line PPC reflects constant opportunity cost, as the uniform slope shows fixed trade-off ratios per economic definition.

Why the others are wrong:

• B shows a concave (bowed-out) curve, indicating increasing opportunity costs.
• C displays a convex (bowed-in) curve, suggesting decreasing opportunity costs.
• D has a nonlinear or irregular shape, not fitting constant costs.

Final answer: A