4. Which one of the following statements on the causes of the energy efficiency gap is correct?

a. The likelihood of buying an energy-efficient refrigerator is higher if a consumer perceives a discount rate that is much higher than the market discount rate.

b. Bounded rationality implies that consumers make decisions by comparing benefits and costs.

c. The principal/agent issue points out the possibility that a tenant is likely to use more energy if the utilities are covered in the rent.

d. If energy markets are not competitive there will be an energy efficient gap.