24. Which of the following types of service transactions is most likely to require the proportional performance method of revenue recognition based on the seller's direct costs to perform each act?a. Processing of monthly mortgage payments by a mortgage bankerb. Providing lessons, examinations, and grading by a correspondence schoolc. Providing maintenance services on equipment for a fixed periodic feed. Delivering freight (by a trucking firm)ANS: B PTS: 1 DIF: