The "percent of sales method" is a method of preparing pro forma financial statements. Which of the following would be an example of how the "percent of sales method" is developed?

a. Forecast expenses by applying a percent of projected sales, using last year's expenses as a percent of last year's sales.
b. Forecast assets by applying a percent of projected sales, using current year's assets as a percent of current year's sales.
c. Approximate liabilities by applying a percent of projected sales, using the last five-year average of liabilities as a percent of sales.
d. All of the above.
e. None of the above.