Correct option is D
The correct answer is (d) Megasthenes.
Megasthenes was sent as an ambassador by Seleucus I Nicator, one of Alexander the Great's generals, to the court of Chandragupta Maurya around 302 BCE.
Megasthenes was the author of ‘Indica’, an account of India under the reign of the Maurya dynasty.
He was an ancient Greek historian and diplomat.
His work provides valuable insights into the society, economy, and governance of ancient India.