Please help, 100 points! Most scientists agree that life began on earth approximately 3.5 billion years ago. What would a scientist need to do in order to test this hypothesis and gather evidence?

A: Recreate the composition of the atmosphere and oceans on Earth as they were 4.5 billion years ago.
B: Travel to a similar planet or moon in its own early formation and recreate the chemical reactions which took place on Earth.
C: Gather the raw materials, such as inorganic compounds, on Earth 4.5 billion years ago and recreate the chemical reactions that could have taken place.
D: This is not a testable hypothesis since there is no way to travel back 4.5 billion years or to run the experiment for the next 4.5 billion years. (This one is obviously wrong)