A system administrator has connected an external USB drive to a computer to transfer some documents. When booting the computer, the system tries to boot from the external drive and gives an error message. Which of the following would be the BEST way to prevent the USB drive from booting?

A. Modify the BIOS to boot from the internal hard drive
B. Modify the boot order in Windows Disk Management
C. Rebuild the MBR on the external hard drive
D. Disable the external drive in Device Manager