I think it's Photosynthesis because photosynthetic bacteria began producing excess oxygen, which added oxygen to the Earth's atmosphere.
Hi there!

Composite volcanoes, shield volcanos, and cinder cone volcanos are all different types of volcanos found on the Earth's surface.
Igneous is a type of rock typically produced by volcanoes, so it is not a type of volcano.
Therefore, the correct answer is B. Igneous.
Hundreds or thousands of years.
Answer:
C. The yellow butterflies were not eaten by birds and were able to reproduce more.
Explanation:
what we can conclude from the passage that the yellow butterflies reproduced more.