Who among the following is the author of the book 'Rajatarangini'?

Kalhana is the author of Rajatarangini ("The River of Kings"), composed in Sanskrit between 1148 and 1150 CE. It is a metrical chronicle providing a detailed history of the kings of Kashmir. It is highly regarded by historians for its attempt at a chronological and objective historical narrative, which was rare in ancient Indian literature.

• Bilhana: An 11^th-century poet from Kashmir who wrote Vikramankadevacharita in honor of the Western Chalukya King Vikramaditya VI.
• Banabhatta: The Asthana Kavi (court poet) of King Harshavardhana; he authored Harshacharita and Kadambari.
• Bhavabhuti: An 8^th-century Sanskrit scholar and dramatist known for works like Uttararamacharita and Malatimadhava.