Correct option is C
Given: Selling a book at 16/25 of the marked price results in a loss.
Formula Used: Marked Price / Selling Price = Ratio of Marked Price to Selling Price
Solution: Let the marked price be M and the selling price be S. S = 16/25 M The ratio of marked price to selling price = M / S = 25 / 16 Therefore, the correct answer is 25:16.