Best telephoto lens for l mount?

Here is what the site says about that.

From Canon EF 70-200mm f/4L USM: Canon EF 70-200mm f/4L USM: A zoom lens by Canon for Full frame cameras, 70-200mm f/4. A light L telephoto without stabilisation, a classic used buy.

From L-Mount: L-Mount: An alliance mount: Leica, Panasonic and Sigma bodies and lenses all fit each other. Sigma's MC-21 adapts Canon EF lenses with autofocus.

Quoted from this site's pages.