单项选择题 You work in a company which uses SQL Server 2008. You are the administrator of the company database. Now you are in charge of a SQL Server 2008 instance. There is a database named DB1 in the instance. When you are absent, a user will use a login named Mary to log in and maintain the database snapshots. The user has to delete the database snapshots for DB1, so you have to give the appropriate permissions to the user.  So which database permission should you give the user?（）

单项选择题 You work in a company which uses SQL Server 2008. You are the administrator of the company database. Now you are in charge of a SQL Server 2008 Enterprise Edition instance. There is a database named DB1 in the instance. A backup of DB1 is performed every day. You have to minimize the size of the full database backup files of DB1.  In the options below, which Transact-SQL statement should you use? （）

单项选择题 You work in a company which uses SQL Server 2008. You are the administrator of the company database. Now you are in charge of a SQL Server 2008 instance. There is a database named DB1 in the instance. The latest differential backup is performed at 15:30, the full back up was performed at 13:30, and database snapshots were created at 16:30 and at 17:30. The backups and the database snapshots are stored on a different disk from the database files. At 17:05, the hard disk containing the database files fails at 17:02 hours. You must restore DB1 while reduce data loss to the least.  So what action should you perform to achieve this goal? （）