The correct options are
A Songs about Chhatrapati Shivaji.
B Palaces constructed by the Marathas.
C Books at the archives in Maharashtra.
Palaces, books, and songs would comprise archaeological, literary, and oral sources of the history of the Marathas. However, the concept of newspapers had arrived in India long after the Marathas rule had ended. Rakesh could, however, find articles already published in newspapers about the Marathas later.