The correct answer is: Both (A) and (B).
Mudrarakshasa is a Sanskrit play written by Vishakhadatta in the 6th century CE. It is set in the 4th century BCE and tells the story of the rise of Chandragupta Maurya to the throne of Magadha. The play is a valuable source of information about the Mauryan Empire and its founder.
Parishishtaparvan is the eighteenth book of the Mahabharata. It tells the story of the Kurukshetra War and its aftermath. The book is a valuable source of information about the political and social history of India in the 5th century BCE.
Both Mudrarakshasa and Parishishtaparvan mention the alliance between Chandragupta and Parvatak. In Mudrarakshasa, Parvatak is the king of the Nagas. He is a powerful and wise ruler who helps Chandragupta to defeat his enemies. In Parishishtaparvan, Parvatak is the king of the Gandharvas. He is a skilled warrior who helps Chandragupta to win the Kurukshetra War.
The alliance between Chandragupta and Parvatak was a significant event in Indian history. It helped to establish the Mauryan Empire as a major power in the region. The alliance also showed the importance of cooperation between different groups in order to achieve common goals.