Which of the following is consistent with the implications of the production possibilities curve?

a. If the resources in an economy are being used efficiently, scarcity will not be a problem.

b. If the resources in an economy are being used efficiently, more of one good can be produced only if less of another good is produced.

c. Producing more of any one good will require smaller and smaller sacrifices of other goods as more of that good is being produced in an economy.

d. An economy will automatically attain that level of output at which all of its resources are fully employed.

e. Both b and c are consistent with the implications of the production possibilities curve.