Why Correct: Ballal Sen, the second ruler of the Sen dynasty who reigned from approximately 1160 to 1179 CE, formally established the Kaulinya system to regulate marriage practices among Bengali Brahmins based on genealogical purity and social status.
Distractor Analysis: Gopala founded the Pala dynasty in the 8th century, centuries before the Kaulinya system emerged. Lakshmana Sen succeeded Ballal Sen and expanded the system's implementation but did not introduce it. Dharmapala was a prominent Pala ruler in the late 8th to early 9th centuries, predating the Sen dynasty entirely.
Takeaway: The Kaulinya system created a rigid social hierarchy where only Brahmins with documented pure lineage for 14 generations could marry within their own group, profoundly influencing Bengali caste structure for centuries.