Explanation:

The correct answer is option 'A', Therigatha, which is not a part of early Jains literature. The Therigatha is actually a collection of poems written by Buddhist nuns and is considered a part of the Theravada Buddhist literature, not Jain literature.

Jain Literature:
Jain literature refers to the religious texts and scriptures of Jainism, an ancient Indian religion. These texts contain the teachings, principles, and philosophy of Jainism, as well as the biographies of Jain Tirthankaras (spiritual teachers) and other prominent figures in Jain history. Jain literature is written in various languages, including Sanskrit, Prakrit, and Apabhramsha.

Early Jain Literature:
Early Jain literature can be classified into two major categories:

1. Agamas:
- Agamas are the primary Jain scriptures and are believed to have been directly preached by the Tirthankaras.
- They are written in Ardha Magadhi, an ancient language.
- The Agamas consist of various texts, including the Angas, Upangas, and Prakirnakas.
- These texts contain the teachings, doctrines, and ethical principles of Jainism.

2. Angas:
- The Angas are the oldest and most authoritative texts in Jainism, considered to be the limbs of the main scripture.
- They consist of 12 texts, including Acharanga Sutra, Sutrakritanga, and Brihatkalpasutra.
- The Acharanga Sutra deals with ethical conduct and discipline.
- The Sutrakritanga focuses on the code of conduct for monks and nuns.
- The Brihatkalpasutra provides guidelines for the performance of rituals and ceremonies.

Conclusion:
In conclusion, the Therigatha is not a part of early Jain literature. It is actually a collection of poems written by Buddhist nuns and is considered a part of the Theravada Buddhist literature. The early Jain literature consists of Agamas, which include texts like Acharanga Sutra, Sutrakritanga, and Brihatkalpasutra, among others.