Indigo cultivation in India declined by the beginning of the 20th century because of

The correct answer is B, its unprofitability in the world market because of new inventions. Indigo lost its market when chemists learned to make the dye in a factory, so the Indian crop became unprofitable and cultivation shrank. Adolf von Baeyer worked out the structure of indigo in the eighteen eighties and the German firm BASF began selling synthetic indigo in 1897; within a few years it had taken most of the world trade, because the manufactured dye was cheaper and of a steadier quality than the plant extract. Bengal and Bihar, which had lived on indigo exports, saw acreage collapse in the first decade of the twentieth century. A is wrong because the Indigo Revolt of 1859 in Bengal and the Champaran satyagraha of 1917 checked the planters in particular districts but did not end the industry. C is wrong because national leaders raised the cultivators' grievances, not a case against the crop. D is wrong because the Government protected the planters rather than curbing them. Exam tip: synthetic indigo from Germany, 1897, killed the natural dye trade.