I solved this problem by following the steps below.
Display screen graphics controller (G): VBoxSVGA selected.
$ sudo apk add xf86-video-vboxvideo xf86-video-intel xf86-video-vesa $ sudo apk add xf86-input-synaptics $ sudo apk add virtualbox-guest-additions $ sudo rc-update add virtualbox-guest-additions default $ sudo echo vboxpci >> /etc/modules $ sudo echo vboxdrv >> /etc/modules $ sudo echo vboxnetflt >> /etc/modules $ sudo apk update $ sudo apk upgrade --update-cache --available $ sudo reboot