An important demand of the Paliyam Satyagraha led by T.K. Madhavan was:

Access to water
Right to vote
End of bonded labor
Entry into government schools

The correct answer is: C) End of bonded labor.

The Paliyam Satyagraha was a non-violent protest led by T.K. Madhavan in 1924 against the practice of bonded labor in the Paliyam village in Kerala, India. The protesters demanded that the government abolish the practice of bonded labor, which was a system in which poor people were forced to work for landowners in exchange for food and shelter. The protest was successful, and the government abolished the practice of bonded labor in 1924.

The other options are incorrect because they were not important demands of the Paliyam Satyagraha. Option A, access to water, was not a major demand of the protest because the people of Paliyam had access to water. Option B, the right to vote, was not a major demand of the protest because the people of Paliyam were not allowed to vote at the time. Option D, entry into government schools, was not a major demand of the protest because the people of Paliyam had access to government schools.