Which statement best explains the gross margin method? a) A method of estimating the cost of ending inventory by applying average sales margin to the retail price of products,
b) this method is least appropriate for inventory items that are not distinguishable from one another,
c) a method that assigns costs to invetories and costs of sales based on actual costs of each item,
d) a method for estimating cost of goods sold by applying an average gross margin to the amount of sales recorded in a period.