Greek-Roman art refers to the artistic styles and techniques that were developed and practiced in ancient Greece and Rome. These art forms were known for their realism and naturalism. While it is true that Greek-Roman art has influenced various regions and cultures, it is most prominently seen in the art of Buddhism.

Buddhist art, particularly in regions like Gandhara, was heavily influenced by Greek-Roman artistic traditions. The Gandhara region, located in present-day Pakistan and Afghanistan, was a major center for Buddhist art. The artists in this region incorporated elements from Greek-Roman art, such as realistic human figures and detailed sculptural techniques, into their Buddhist artwork.

While the Ellora and Kalinga regions in India have their own distinct artistic traditions, Greek-Roman art did not find as significant a place in these regions as it did in Buddhist art. Therefore, option 4 - Buddhist art is the correct answer.