Currently there are 21 native Telephoto Zoom lenses for Sony A7c and 20 of these lenses are autofocus (AF) type.
A7c also has a sensor based image stabilization system which means that all of these lenses will be stabilized when used on A7c.
Since Sony A7c has environmental sealings (Weather Sealing), you may like to couple your camera with one of these 18 Telephoto Zoom lenses with Weather Sealings.