How Do Scientists Study the History of Life on Earth

Multiple Choice

How do scientists study the history of life on Earth?

A) by studying fossils, the preserved remains of past organisms
B) by using telescopes to look far away, and thus see what life was like in the past
C) by comparing present- day organisms with each other, and assuming past life had mixed traits of present- day organisms
D) by assuming that life in the past was just like present- day life