Answer:
Without an oxygen atmosphere very few things could live on the early Earth. Anaerobic bacteria were probably the first living things on Earth. The early Earth had no oceans and was frequently hit with meteorites and asteroids.
Explanation:
Exo means outside
So planets outside our solar system
<span>Letter A is the answer. Almost all plant cells have single large central vacuole. These large central vacuoles of the plant cells are filled with water and can take over 80% of its cell volume. This is surrounded by a single membrane called tonoplast. The role of the central vacuole is maintaining the plant cell's pressure.</span>
