Assume the below information about a firms defined benefit pension plan: Pension Fund Beginning Balance Cash Funding by the Firm Actual Investment Income Payments to Retirees Ending Balance 2 + 5 - 15 42 Pension Obligation Beginning Balance Service Interest Payments to Retirees Changes in Assumptions Ending Balance 9 5 0 49 Expected investment income was greater than actual investment income by $5. What was the funded status of the pension plan at the beginning of the year? Select one: a. Underfunded by $15 b. Overfunded by $10 c. Fully funded d. Underfunded by $10