XYZ Company is currently selling its single product for $15. Variable costs are estimated to remain at 70% of the current selling price and fixed costs are estimated to be $4,800 per month. If XYZ decreases its selling price by 10%, its contribution margin ratio will: Select one: a. None of the given answers. O b. decrease. O c. not change. O d. increase. O e. Cannot determine with the information given