Final answer:
The journal entry for Complete Computer Service's rent payment records a debit to Rent Expense and a credit to Cash for $900.
Step-by-step explanation:
The journal entry to record the payment of $900 for rent expense for the current month by Complete Computer Service would be:
- Debit Rent Expense $900
- Credit Cash $900
This entry reflects the decrease in cash due to the rent payment and records the expense for the current period. As this is a cash transaction, the impact is immediate on the company's financial statements, reducing both their cash balance and the equity (as expenses reduce net income).