The Trial Balance for Greenway Corporation Appears as Follows $\begin{array}{lrr}\end{array}$

The trial balance for Greenway Corporation appears as follows:
$\begin{array}{lrr}\end{array}$

$\begin{array}{lrr}& \text{ \textbf{ Greenway Corporation }\ } \\& \text{ Trial Balance}\\ &\text{ \underline{\text{ December 31,2014}} } \\\\ \text{ Cash } .................................................................& \$ 300 & \\\text{ Accounts Receivable } ........................................ & 500 & \\\text{ Prepaid Insurance } ........................................... & 60 & \\\text{ Supplies } ........................................................ & 140 & \\\text{ Equipment } ....................... & 4,000 & \\\text{ Accumulated Depreciation, Equipment }......... & & \$ 800 \\\text{ Accounts Payable } ........................................ & & 300 \\\text{ Common Stock} ..............................................& & 1,000 \\\text{ Retained Earnings }.......................................... & & 1,400 \\\text{ Service Revenue } .......................................... & & 3,000 \\\text{ Salaries and Wages Expense } .......................& 1,000 & \\\text{ Rent Expense } ..............................................& \underline{\text{500 }} & \underline{\text{0 }} \\\text{ } & \$6,500 & \$6,500 \\ \end{array}$
If service for $125 had been performed but not billed, the adjusting entry to record this would include a:

A) debit to Service Revenue for $125.
B) credit to Unearned Service Revenue for $125.
C) credit for Service Revenue for $125.
D) debit to Unearned Revenue for $125.