Explanation:

- Hsuan Tsang:

- A Chinese Buddhist monk and scholar.

- Visited India during Harshavardhana's reign in the 7th century.

- His visits vastly contributed to the understanding of Indian history and Buddhism.

- Etsing:

- Another Chinese monk who traveled to India.

- Arrived after Hsuan Tsang, in the 7th century, but later in the time period of Harsha's rule.

- Faxian:

- A Chinese Buddhist monk and traveler.

- Visited India in the 5th century, before the reign of Harshavardhana.

- Ibn Battuta:

- A Moroccan explorer, not Chinese.

- Visited India in the 14th century, much later than Harshavardhana's era.