The Justice Party was a political movement in Tamil Nadu that challenged:

The correct answer is: b) Caste-based discrimination.

The Justice Party was a political party in British India that was founded in 1916. The party was formed by a group of non-Brahmin leaders who were opposed to the dominance of Brahmins in the Indian National Congress. The Justice Party campaigned for social and political reforms, including the abolition of caste-based discrimination. The party was successful in winning a number of seats in the Madras Legislative Council, and it played a significant role in the development of Tamil Nadu.

The other options are incorrect because:

• a) British colonial rule was challenged by a number of different political movements, including the Indian National Congress.
• c) Economic inequality was a major issue in India, but it was not the primary focus of the Justice Party.
• d) Linguistic divisions were also a major issue in India, but they were not the primary focus of the Justice Party.