b. What were Costco operating and net profit margins in that year? How do they compare with its margins in the prior year? (Select the best choice below) OA. Operating profit margin was 3.10% while net profit margin was 2.40%. The former decreased while the latter increased with respect to those of the prior year OB. Operating profit margin was 3.16% while net profit margin was 2.21%. The former decreased while the latter increased with vespect to those of the prior year. C. Operating profit margin was 3.19% while net profit margin was 2.08%. The former decreased while the latter increased with respect to those of the prior year D. Operating profit margin was 3 02% while net profit margin was 2.12%. The former decreased while the latter increased with respect to those of the prior year