Why is my wifi option not available after upgrading to Windows 10 from 8.1?

[Windows Central Question]

why my wifi option is not available after upgrading to windows 10 from 8.1

i have been using windows 10 from past 2 weeks. the internet connectivity was fairly good. suddenly my wifi option disappeared from the network option. i cannot connect to internet through my dongle too. after troubleshooting the problem through network connections it says that there might be a problem with the driver for the wifi adapter.