单项选择题 Certkiller.com has asked you to create an application to display all of the top directories based on the drive path.You need to ensure that the application displays the number of files within top-level directories.What should you do?（）

单项选择题 Certkiller .com has asked you to develop an application that displays the properties for all Certkiller.coms network drives. The information generated by this application will be utilized by Certkiller .coms network administrators to verify client setups. You need to ensure that these requirements are fully satisfied. What should you do?（）

单项选择题 You have recently completely creating a new application for Certkiller .com. This new application has to load an instance of the Inventory class from a large file named Inventory.dat. You need to ensure that the application executes the loading process in as little time as possible. What should you do?（）