Explanation:

- Mathura: This city was a major centre of art and sculpture during the Gupta period, known especially for its red sandstone sculptures.

- Sarnath: Renowned for its school of sculpture, Sarnath produced some of the finest examples of Gupta art, particularly Buddhist imagery.

- Patliputra: As the political capital, Patliputra fostered artists and craftsmen, and was a noted centre for sculpture in the Gupta age.

- Bodh-Gaya: Though significant for Buddhist spirituality and pilgrimage, Bodh-Gaya was not a recognized centre for sculpture art in the Gupta period.

Correct Answer: Option 4, Bodh-Gaya