iOS setting correct resolution in project settings

In previous versions of Unity, you could find an option in Project Settings → Player → Other Settings to set the target resolution to native. However, in recent versions, this specific option seems to be missing, even though you can still set target devices like iPad and iPhones. Does this mean Unity now does this by default?

In my in-game settings menu, I’ve configured it so that the “high” setting corresponds to 100% of the native resolution, “medium” to 75%, and “low” to 50%. Before a user messes with those settings, how can I ensure that the resolution defaults to 100% of the native resolution when the game is initially installed and launched?