Which Indian emperor is traditionally credited with writing the Sanskrit play Nagananda?

Introduction / Context:
Nagananda is a famous Sanskrit play that is significant for combining dramatic art with Buddhist themes of compassion and self sacrifice. It is traditionally attributed to a renowned emperor of North India. Linking literary works with their royal authors is a common type of general knowledge question, especially within the cultural history of ancient and early medieval India.

Given Data / Assumptions:

• The literary work mentioned is the Sanskrit play Nagananda.
• The options list several rulers: Prabhakaravardhana, Harshavardhana, Chandragupta II, Bindusara and Pulakeshin II.
• We must identify which of these emperors is traditionally regarded as a poet playwright.
• Other rulers are famous for political or military achievements rather than for writing Sanskrit drama.

Concept / Approach:
The central concept is the cultural profile of Emperor Harshavardhana, who ruled North India in the seventh century. Literary tradition credits him with authoring at least three plays: Nagananda, Ratnavali and Priyadarsika. This makes him stand out among the rulers listed. Recognising Harshavardhana as a scholar and playwright as well as a king allows us to choose the correct option.

Step-by-Step Solution:

Verification / Alternative check:
History and literature reference books commonly mention Harshavardhana as an author king. Chinese traveller Xuanzang praised Harsha for his patronage of learning and religion, supporting the idea that his court was a centre of culture. Listings of Sanskrit plays attribute Nagananda to Harsha, while the other rulers in the options are not associated with such works. This cross verification confirms the answer.

Why Other Options Are Wrong:

• Prabhakaravardhana: Known as Harsha's father and a ruler of Thanesar, but with no major literary works attributed to him.
• Chandragupta II: A Gupta emperor famous for political expansion and cultural patronage, but not for personally writing Nagananda.
• Bindusara: A Maurya ruler and father of Ashoka, not connected with Sanskrit drama in this way.
• Pulakeshin II: A celebrated Chalukya king who resisted Harsha's expansion, again not known as a playwright.

Common Pitfalls:
Some students may confuse the cultural patronage of emperors with direct authorship and may assume that any golden age ruler wrote famous works. Another pitfall is mixing up Harsha with other learned kings. The safest method is to memorise a short list of royal authors, among whom Harshavardhana stands out for writing Nagananda and other plays.

Final Answer:
Correct answer: Harshavardhana.