Dmitry Installs the Hyper-V Role Using the Add Roles and Features

Dmitry installs the Hyper-V role using the Add Roles and Features Wizard. Upon completion, he is prompted to reboot the computer. However, his computer reboots twice. Why does Dmitry's computer reboot the second time?

A) To allow Hyper-V to start the Kerberos protocol
B) To allow Hyper-V to start the host operating system
C) To add Hyper-V in a Type 2 configuration
D) To add Hyper-V in a Type 1 configuration