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 management data warehouse that uses the data collector to collect performance data. You intend to maintain the management data. You want to implement a data collection process. The process can gather and upload data in the management data warehouse on different schedules.  What process should you implement？（） 

• A、You should create a cached data collection
• B、You should create an on-demand non-cached data collection 
• C、You should create a scheduled non-cached data collection 
• D、You should create two different SQL Agent jobs that are scheduled stimultaneously