Emperor Harsha's southward march was stopped on the Narmada River by

1. The question asks which ruler stopped Emperor Harsha's southward march on the Narmada River. 2. Emperor Harshavardhana of Vardhana dynasty attempted to expand his empire into the Deccan region. 3. His advance was halted by Pulakesin-II, the powerful Chalukya king of Badami. 4. The battle took place on the banks of the Narmada River, likely around 618-619 CE or slightly later. 5. The Aihole inscription of Pulakesin-II mentions his victory over Harsha. 6. Therefore, the correct answer is (B) Pulakesin-II.