To set as the Lock Screen Wallpaper:
Tap on Settings, Wallpapers & Brightness, Choose a New Wallpaper. Choose the photo from the camera roll and set as Lock Screen.
I had to ‘pinch’ to adjust the size of the jpeg, but it uploaded just fine.
A huge thank you to Laura Strickland from MyCuteGraphics for the wonderful clip art and backgrounds. www.mycutegraphics.com