Which of the following is the PRIMARY factor which contributed to the emergence of multiple political parties at the same level in India?

The PRIMARY factor behind the emergence of multiple political parties at the same level in India is:

(c) linguistic and regional diversity.

Explanation:
India’s diverse linguistic and regional fabric led to the formation of multiple political parties at the same level. Different regions with unique languages and cultures gave rise to parties representing these diverse interests. This diversity fostered the emergence of parties aligned with specific regional or linguistic groups, influencing India’s political landscape with a multitude of parties at similar levels.