4. Ancient cyanobacteria released ______, which assisted in creating the atmosphere as we know it today.
A. oxygen
B. lead
C. hydrogen
D. ore
A?
Reed told me yes for A,but I still was not sure!
4 answers
I'm not Ms.Sue, but you're correct. :)
Thanks I will go with this answer and tell you if it was right.☺
The answer is a because Cyanobacteria are photosynthetic organisms, like plants, they produce sugars and O2 from carbon dioxide and water (..and energy from sunlight).
You were right.