The correct option is "Only two pairs," as Aryadeva is primarily recognized as a prominent Buddhist scholar rather than a Jaina scholar, which makes the first pair incorrectly matched. Dignaga, a significant figure in Buddhist logic, and Nathamuni, known for his contributions to Vaishnavism, are appropriately matched with their respective traditions. This distinction emphasizes the diverse philosophical traditions that flourished in ancient India and is crucial for understanding the historical and cultural interactions between Buddhism, Jainism, and Hinduism, as covered in standard UPSC materials like NCERTs.