Final answer:
The White Drin River is the largest river that is wholly contained within the borders of Kosovo.
Step-by-step explanation:
The largest river that is wholly in Kosovo is the Drini i Bardhë or White Drin River. It originates in the Çakorr mountains of Kosovo and flows through the country before reaching its confluence with the Black Drin in northern Albania, where both rivers form the Drin, which eventually drains into the Adriatic Sea. The White Drin River is significant not only for its size within the territory of Kosovo but also for its role in the local ecosystem and hydrology.