Explanation:

The word "Jaina" comes from the term "Jina."

Definition of Jina:
- The term "Jina" is derived from the Sanskrit word "ji," which means "to conquer" or "to overcome."
- In Jainism, a Jina refers to a spiritual conqueror or a liberated soul who has conquered the cycle of birth and death.

Jainism:
- Jainism is an ancient Indian religion that emphasizes non-violence, truth, and asceticism.
- The followers of Jainism are known as Jains.
- Jainism advocates for the liberation of the soul from the cycle of birth and death through spiritual practices, self-discipline, and renunciation.

Origin of the Word "Jaina":
- The word "Jaina" is a noun that refers to a follower of Jainism.
- It is derived from the term "Jina," which is used to describe the liberated souls revered in Jainism.
- The suffix "-a" is added to "Jina" to indicate a person or follower.
- Therefore, a Jaina is someone who follows the path of the Jinas and Jainism.

Other Options:
a) Jana: The term "Jana" means "people" or "community" in Sanskrit. It is not directly related to the word "Jaina" or Jainism.
b) Jinaya: The term "Jinaya" is not commonly used in the context of Jainism. It is not the origin of the word "Jaina."
d) Jain: The term "Jain" is derived from the word "Jina" and is used to refer to a follower of Jainism. However, it does not explain the origin of the word "Jaina."

Therefore, the correct answer is option "C" - Jina. The word "Jaina" is derived from the term "Jina," which refers to the liberated souls in Jainism.

The answer is {d} jain as the followers of Mahavira was called jaina