Correct Option: B

Seleucus I Nicator was a leading officer of Alexander the Great’s League of Corinth and one of the Diadochi. In the Wars of the Diadochi that took place after Alexander’s death, Seleucus established the Seleucid dynasty and the Seleucid Empire. He was defeated by the emperor of India, Chandragupta Maurya and accepted a matrimony alliance for 500 elephants after ceding the territories considered as part of India.