Correct Option: C Megasthenes was a Greek ethnographer and explorer in the Hellenistic period, author of the work Indica. He was born in Asia Minor (modern day Turkey) and became an ambassador of Seleucus I of the Seleucid dynasty possibly to Chandragupta Maurya in PataliputraPataliputraDuring the Mauryan period, the city was described as being shaped as parallelogram, approximately 2.5 kilometers (1.5 miles) wide and 15 kilometers (9 miles) long. Its wooden walls were pierced by 64 gates.
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