A technician is installing a memory upgrade for a remote user. The technician notes that the machine is not reporting the correct amount of memory that was installed during the POST step. Which of the following actions should the technician perform FIRST?（）

• A、Replace the newly installed memory modules with another known-working unit.
• B、Remove and reseat the memory, and recheck the memory reported.
• C、Leave the configuration intact, and check cabling to ensure nothing was loose during the installation.
• D、Perform a BIOS upgrade on the machine.