The correct answer is: A. a-1, b-2, c-3
Gram Panchayat is the lowest level of Panchayati Raj Institution (PRI) in India. There are a total of 243,000 Gram Panchayats in India. Zilla Parishad is the intermediate level of PRI. There are a total of 625 Zilla Parishads in India. Panchayat Samiti is the intermediate level of PRI. There are a total of 5,873 Panchayat Samitis in India.
Option A is the only option that matches the number of PRIs with the correct level of PRI. Option B has the wrong number of Gram Panchayats. Option C has the wrong number of Panchayat Samitis. Option D has the wrong number of Zilla Parishads.