Vernon Car Corp. (VCC), a public company, has a defined benefit pension plan for its employees. Lupe, VCC's controller, is researching how the plan asset returns under a defined benefit plan are treated. Which of the following statements is true regarding VCC's plan assets for the defined benefit plan?

a) The actual pension plan returns are recorded as revenue on VCC's statement of comprehensive income.
b) A portion of plan returns is recorded as a reduction to the pension expense for VCC.
c) The actual pension plan returns increase VCC's net pension liability.
d) Differences between the expected and actual returns on the plan assets are recorded to profit or loss of VCC.