You design a Business Intelligence （BI） solution by using SQL Server 2008. You create a SQL Server 2008 Reporting Services （SSRS） solution. The solution contains a report named Sales Details that displays sales information of all the employees. You create an SSRS report named Sales Summary that displays the total monthly sales of each employee. Users who view the Sales Summary report occasionally require the monthly sales details for a particular employee. You need to ensure that the users can click a value in the month column of the Sales Summary report to open and render the Sales Details report. What should you do？（）
- A Use a subreport.
- B Use a bookmark link.
- C Use the drilldown functionality.
- D Use a drillthrough report link.