The statement that should be attached to the arrow pointing downwards is B. 20 million Americans attended.
What was the First Earth Day in 1970?
The first Earth Day was celebrated on April 22, 1970, and it was a significant event that marked the beginning of the modern environmental movement. In 1969, Senator Gaylord Nelson witnessed the devastating effects of an oil spill in Santa Barbara, California.
This event inspired him to create a national day to raise awareness about environmental issues. 20 million Americans participated in the events on that day across the country.