The correct answer is: B. Gupta
Nalanda flourished in the 5th century AD as an educational center during the Gupta Empire. The Gupta Empire was a golden age for India, and Nalanda was one of the most important universities in the world at that time. It was a center of learning for Buddhist, Hindu, and Jain scholars.
The Mauryan Empire was a powerful empire that ruled over much of India from the 4th century BC to the 2nd century BC. The Mauryan Empire was not a time of great intellectual or cultural achievement, and Nalanda was not a major center of learning during this time.
The Later Mauryan Empire was a short-lived empire that ruled over parts of India from the 3rd century AD to the 4th century AD. The Later Mauryan Empire was not a time of great intellectual or cultural achievement, and Nalanda was not a major center of learning during this time.
The Later Gupta Empire was a short-lived empire that ruled over parts of India from the 5th century AD to the 6th century AD. The Later Gupta Empire was a time of great intellectual and cultural achievement, and Nalanda was one of the most important universities in the world at that time.