The following persons came to India at one time or another: I. Fa-Hien II. I-Tsing III. Megasthenese IV. Hieun-Tsang The correct chronological sequence of their visits is:

The correct chronological order is determined by the historical periods in which these travelers visited India. First was Megasthenes, a Greek ethnographer and ambassador who visited during the 4th century BC during the reign of Chandragupta Maurya. Second was Fa-Hien, a Chinese Buddhist monk who visited during the early 5th century AD during the reign of Chandragupta II of the Gupta Dynasty. Third was Hieun-Tsang, also known as Xuanzang, a Chinese Buddhist monk who visited during the 7th century AD during the reign of King Harshavardhana. Fourth was I-Tsing, a Chinese Buddhist traveler who visited later in the 7th century AD, shortly after Hieun-Tsang had left. Therefore, the correct sequence is III, I, IV, II, making option B the correct answer.