Choice "A" is correct. It is easier to access and alter microcomputer data files than manually prepared data files. Microcomputer access security is difficult to maintain because of the increased number of data entry points and the potential ability to defeat access controls.
Choice "c" is incorrect. Once the programs are written, the focus will still be on the accuracy of the transactions.
Choice "b" is incorrect. One of the benefits of an automated system over a manual system is the removal of random errors from the process. (Instead, systematic errors are more common.)
Choice "d" is incorrect. There is no significant difference between comparing physical counts with accounting records kept either manually or on an automated system.