When was the first year Earth Day was recognized?

I work best on a deadline so I start projects close to their due date.

A.) 1967

A.) 1967

I work on the tasks that I enjoy most first.

B.) 1969

B.) 1969

I work on the tasks that I enjoy most first.

C.) 1970

C.) 1970

I work on the tasks that I enjoy most first.

D.) 1972

D.) 1972