Answer:
A) August 31
Step-by-step explanation:
The revenue recognition principal states that a company should only recognize revenue when it has substantially completed the earning process. This earning process can be completed either before or after receiving the payment. If it is completed before receiving payment, an accounts receivable is created. But if the good or service was paid in advance, an accounts payable is created until the good or service is delivered or completed.
In this case, Otto completed the earning process either August 31 or September 1, it is not clear when the car service was completed, but since September 1 is not an option, then the only possible option is August 31.