Who was a key figure in the american school of philosophy known as transcendentalism?

The answer is Ralph Waldo Emerson.

Explanation:

Ralph Waldo Emerson was the most important figure of the transcendentalist movement during the mid-19th century. He was born in Boston, Massachusetts, U.S. and he was also a philosopher and a poet. He was considered an important figure regarding individualism as well as a prescient critic of society's pressures.

Emerson published many essays through which he could spread his thoughts as well as dozens of public lectures throughout the United States. He expressed transcendentalism's philosophy through his essay "Nature" in 1836.  

i think its toxic gasses but i could be wrong

answer; i believe it was by president pranab mukherjee or by the chief justice of kerala high court; ///plz check luck