Production possibility curves — practice question

The diagram shows a production possibility curve for an economy that produces capital goods and consumer goods. Why is the production possibility curve shaped concave towards the origin?

• ACapital goods are a more labour-intensive output than consumer goods.
• BConsumers always seek to maximise their satisfaction from consumption.
• CProfit maximisation for firms always ensures efficiency in production.
• DSome resources are more efficient in production of some goods than others.