The ancient buildings named Ratnasagara, Ratnadadhi and Ratnaranjaka were part of which of the following universities of ancient India?

Ratnasagara, Ratnadadhi and Ratnaranjaka were the great library buildings of Nalanda.

Takshashila was an earlier centre but not the site of these named halls.

Odantapuri was another Buddhist monastery, without these library buildings.

Sri Dhanya Katak was a southern seat of learning, not connected to them.

These three structures formed the vast library complex known as Dharmaganja.

Nalanda's library was famed across Asia for its manuscript collection.