Who was the last ruler of Dev dynasty?

The correct answer is: B. Bairam Dev

Bairam Dev was the last ruler of the Dev dynasty. He was the son of Braj Raj Dev and ruled from 1552 to 1562. He was defeated by Akbar in 1562 and the Dev dynasty came to an end.

A. Jit Singh was the ruler of the Amber state from 1526 to 1540. He was the son of Prithviraj Singh and the father of Raja Man Singh.

Braj Raj Dev was the ruler of the Dev dynasty from 1540 to 1552. He was the son of Jit Singh and the father of Bairam Dev.

D. Duleep Singh was the last Maharaja of the Sikh Empire. He was the son of Maharaja Ranjit Singh and ruled from 1843 to 1849. He was exiled to England in 1849 and died there in 1893.