Explanation:

- Indigo: Indigo was a major plantation crop in India during the early nineteenth century. It was primarily controlled by British planters who exploited local farmers to meet European demand for dye.

- Tea: The British established large tea plantations in India, especially in Assam and Darjeeling. Tea was a key export to Britain and held a prominent place in colonial economy.

- Coffee: Coffee cultivation in India was also developed by British planters, particularly in regions like Karnataka and Kerala. It involved large tracts of land owned by British interests.

- Rubber: Though rubber plantations became significant later, they were not prominent under British management during the early nineteenth century. Rubber emerged as a major plantation crop in India but this occurred prominently in the late nineteenth and early twentieth centuries.

Correct Answer: Rubber