Name the Chalukya king who defeated Harshavardana.
Explanation
Why Correct: Pulakeshin II, the Chalukya ruler of Badami, defeated Harshavardhana of Kannauj on the banks of the Narmada River around 618-619 CE, preventing Harsha's southward expansion.
Distractor Analysis: Pulakeshin I founded the Chalukya dynasty but did not fight Harsha. Mangalesh was Pulakeshin II's uncle and predecessor who expanded the kingdom. Kirtivarmana I was Pulakeshin II's father who consolidated Chalukya power in the Deccan.
Takeaway: The Aihole inscription of Pulakeshin II, composed by his court poet Ravikirti, provides the primary historical evidence for this battle and Chalukya achievements.