Q. Dinabandhu Mitra’s first play _______ exposed the atrocities of the British indigo planters

Answer of this question "Dinabandhu Mitra’s first play _______ exposed the atrocities of the British indigo planters", here are 4 choices for this question : Kulin Kulasarvasva, Ratnavali, Nil Darpan, Ras-lila.
Answer Is "Nil Darpan".