What was the only type of life on planet for hundreds of millions of years?

1. efficient use of space

2. elimination of groundwater contamination

3. energy generation

4. lower carbon footprint

you didn't give any options but heres what i can tell you: an inference is likely to change based on additional observations. the latter is something that you have seen or sensed using your sensory organs while the former is like a conclusion out from what you have observed.

bru what tyep of qus is dis