Unwanted Adds and Apps get installed automatically

[Sharoont2]

Adds pops up on the main screen. As soon as internet is connected, apps get installed by there-self. apps like NetService, GoogleAdds, pro,haha get installed and causes these adds. No matter how many times i uninstalled them they are installed again. Even i hard reset the phone still they are not stopping. Kindly help how to stop this. As i am not able to find which app is specially doing this. And from where these come