The correct answer is (b) Nine.
Rajtarangini is a historical chronicle of the kings of Kashmir, written by Kalhana in Sanskrit. It is divided into eight books, or tarangas, which cover the period from the reign of Pariharochana in the 3rd century BCE to the reign of Harsha in the 7th century CE.
The first taranga deals with the legendary kings of Kashmir. The second taranga deals with the early historical kings of Kashmir, up to the reign of Lalitaditya Muktapida in the 8th century CE. The third taranga deals with the reign of Lalitaditya Muktapida. The fourth taranga deals with the reign of his son, Vajraditya. The fifth taranga deals with the reign of his grandson, Bhimadeva. The sixth taranga deals with the reign of his great-grandson, Kshemagupta. The seventh taranga deals with the reign of his great-great-grandson, Didda. The eighth taranga deals with the reign of her grandson, Harsha.
Rajtarangini is an important source of information on the history of Kashmir. It is also a valuable work of literature, and is considered to be one of the masterpieces of Sanskrit literature.