s 11 to 14 relate to airline leadership in cost efficiency, asset utilization, process design, and new business initiatives. With respect to leadership in cost efficiency, which of the following is not usually considered an important KPI for measuring cost efficiency? Group of answer choices A. Maintenance cost per aircraft B. Aircraft ownership cost per aircraft C. Cost per available seat kilometer (CASK) D. Cost per revenue passenger kilometer (CRPK) E. Cost per number of routes in the network (domestic and international)