Which of the following statements are correct?I Wages paid to production supervisors would be classified as manufacturing overhead.II Indirect costs, such as manufacturing overhead, are always variable costs.I Selling costs are indirect product costs.IV Opportunity costs at a manufacturing company are not part of manufacturing overhead.A$.$ Statements I and IV are the only correct statements.B$.$ Statements I and Ill are the only correct statements.C$.$ Statement III is the only correct statement.D$.$ All of the statements are correct.E$.$None of the statements are correct.