The correct answer is: D. All of these.
Rajtarangini and Vishnu Purana are both ancient Indian texts that contain information about the history of the Kangra Valley. Rajtarangini is a chronicle of the kings of Kashmir, while Vishnu Purana is a Hindu text that contains information about the history of the world. Both texts mention the old tribe of Kangra and the Katoch rulers of Trigarta.
Rajtarangini also contains information about Lalitaditya’s influence on the Kangra Valley. Lalitaditya was a king of Kashmir who ruled in the 8th century CE. He is known for his conquests and for his patronage of art and architecture. He is also credited with building the fort at Nagarkot, which is located in the Kangra Valley.
Persian sources also contain information about Sultan Mahmud’s invasion of Nagarkot. Sultan Mahmud was a ruler of the Ghaznavid Empire who ruled in the 11th century CE. He is known for his military campaigns and for his destruction of Hindu temples. He invaded Nagarkot in 1009 CE and destroyed the fort there.
Therefore, all of the statements in the question are correct.