During the 1400s, the civilization that traded with India was the Swahili Coast. The Swahili Coast, located along the East African coast, engaged in trade across the Indian Ocean, linking Africa to the Indian subcontinent and other regions.
The other options, such as Britain and the United States, were not involved in trade with India during the 1400s, as Britain began to establish trade in the region later in the 16th century, and the United States did not exist as a nation during that time. The Axum Empire, while historically significant, had largely declined by the 1400s and was not known for trade with India at that time.