You use a SQL Server 2005 database named DB1， which is located on a server named SQL1. DB1 is in use 24 hours a day， 7 days a week. A recent copy of DB1 exists on a second server named SQLtest that also runs SQL Server 2005. You detect a high number of full scans on SQL1 and conclude that additional indexes in DB1 are needed. A workload file that is suitable for Database Engine Tuning Advisor （DTA） already exists. You need to analyze the workload file by using DTA. You must ensure maximum performance on SQL1 during analysis. You must also ensure availability during the implementation of any recommendations suggested by the DTA. What should you do？（）

A. Store the workload file on SQL1. Start DTA on SQLtest and connect to SQL1. Specify all workload and tuning options as necessary. In the Advanced Tuning Options dialog box， select the Generate only online recommendations check box.
B. Store the workload file on SQLtest. Start DTA on SQLtest and connect to SQLtest. Specify all workload and tuning options as necessary. In the Advanced Tuning Options dialog box,select the generate only online recommendations check box.
C. Store the workload file on SQL1. Start DTA on SQL1 and connect to SQL1. Specify all workload and tuning options as necessary. In the Advanced Tuning Options dialog box，select the All recommendations are offline check box.
D. Store the workload file on SQLtest. Start DTA on SQLtest and connect to SQLtest.Specify all workload and tuning options as necessary.In the Advanced Tuning Options dialog box,select the All recommendations are offline check box.