Which cine film size is NOT commonly available?

The cine film size that is not commonly available is 70 mm. The 70 mm format is much less prevalent in general filmmaking and is primarily used for specific high-end productions, such as certain types of large-scale or IMAX films. In comparison, 16 mm, 35 mm, and 120 mm films are widely used in various settings, including educational and independent filmmaking, as well as in professional cinema.

16 mm and 35 mm are standard formats that have a rich history in both film industry and amateur filmmaking. The 120 mm format is primarily associated with still photography rather than cinematography, but it is still recognized more frequently than 70 mm in various photography and film contexts. As such, the limited use and specialized nature of 70 mm film contribute to its status as the least commonly available option in the list provided.