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 are queries that have an estimated execution cost less than 3. You intend to configure the instance, make it use a single thread for these queries. In the options below, which sp_configure configuration option should you set?（）

• A、You should set query governor cost limit
• B、You should set cost threshold for parallelism
• C、You should set priority boost 
• D、You should set precompute rank