Will iTunes wipe out my iPhone data if it wants to Set as New iPhone?

I've owned an iPhone 5s for over a year, it's currently running iOS 10.3.3 but I've just connected to iTunes for the first time however I only get 2 options, either "Set it up as new iPhone" or "Restore from an old backup", but that last backup is from 2015. So, if if I select "As New iPhone" will it wipe out my data?

Yes.