Answer: A- Revenue under the installment sales method, as soon as it has assisted Steffi in setting up the store.
Explanation: The installment sales method is a method of accounting accepted under the US Gaap. It is a method were revenue is recorded in instalments and the cost of sales and gross profit recognised upon the collection of the installment revenue.
It is a method of accounting used mainly by construction companies whose revenue are not received once but in installments.