Which of the following statements is false regarding the revenue recognition principle?

a. Revenue must be substantially earned before it is recognized

b. The accountant usually recognizes revenue before the seller acquires the right to receive payment from the buyer.

c. Some small companies use the cash basis of accounting.

d. Under the installment basis, the gross margin recognized in a period is equal to the amount of cash received from installment sales times the gross margin percentage for the year of sale.