Which one among the following states has the highest number of seats in the Council of States?

Among the given options, Bihar has the highest number of seats in the Council of States (Rajya Sabha). Bihar has 16 Rajya Sabha seats, Tamil Nadu has 18, Madhya Pradesh has 11, and Andhra Pradesh has 11. Wait — Tamil Nadu actually has 18 seats. Re-examining: Uttar Pradesh has the most (31), followed by Maharashtra (19), Tamil Nadu (18), Bihar (16), West Bengal (16), and others. Therefore, among the listed states, Tamil Nadu has the highest number with 18 seats in the Council of States.