Which one of the following will result in an accruable expense for an accrual-basis taxpayer?

a. An invoice dated prior to year end but the repair completed after year end.

b. A repair completed prior to year end but not invoiced. A

c. repair completed prior to year end and paid upon completion.

d. A signed contract for repair work to be done and the work is to be completed at a later date.

Explain your answer.