Abanindranath Tagore is the correct answer as he was the main artist of the Bengal School. He was a prominent artist and a key figure in the art movement that came to be known as the Bengal School of Art. Here are the details of Abanindranath Tagore's role in the Bengal School:

Background of the Bengal School:
The Bengal School of Art was a revolutionary art movement that emerged in the early 20th century in Bengal, India. It aimed to revive and redefine Indian art by incorporating elements of traditional Indian art forms, particularly from the Mughal and Rajput schools, as well as folk art. The artists of the Bengal School sought to break away from the dominance of Western art styles and create a distinctive Indian identity in art.

Abanindranath Tagore's Role:
Abanindranath Tagore played a pivotal role in the development and popularization of the Bengal School. He was a nephew of Rabindranath Tagore, the renowned poet, and Nobel laureate. Abanindranath was deeply influenced by the artistic and cultural heritage of India, which is reflected in his works.

Main Artist of the Bengal School:
Abanindranath Tagore was considered the main artist of the Bengal School. He was known for his innovative approach to art and his ability to combine traditional Indian aesthetics with modern techniques. Abanindranath experimented with various styles and mediums, including watercolors, wash technique, and tempera. His paintings often depicted mythological and historical themes, showcasing his deep understanding of Indian culture and heritage.

Indian Society of Oriental Art:
Abanindranath Tagore was not only an artist but also a visionary who aimed to promote and revive Indian art. In 1907, he founded the Indian Society of Oriental Art, with the objective of promoting indigenous art forms and providing a platform for artists to showcase their work. The society played a significant role in nurturing and popularizing the Bengal School of Art.

Legacy and Influence:
Abanindranath Tagore's contributions to the Bengal School and Indian art, in general, were immense. He inspired a whole generation of artists who followed in his footsteps and further developed the Bengal School. His emphasis on Indian aesthetics and cultural identity laid the foundation for the modern Indian art movement. Abanindranath's legacy continues to influence and inspire artists in India and beyond.

In conclusion, Abanindranath Tagore was the main artist of the Bengal School, and his artistic vision and contributions played a crucial role in shaping the movement. His establishment of the Indian Society of Oriental Art further cemented his position as a leading figure in the revival of Indian art.