Which of the following statements about public goods is NOT accurate?

a. The government may be able to overcome the free-rider problem with public goods by providing the public goods and imposing taxes to pay for them.

b. The nature of public goods is such that the government CANNOT accurately assess the benefits and costs of those affected.

c. National defence and flood control are illustrations of public goods.

d. Just as in the case of external costs, public goods tend to be underprovided by the private sector.