Which ones are the most essential for the origin of life?

The theory of abiogenesis or spontaneous generation was finally disapproved by

Assertion: The primitive atmosphere was a reducing one,i.e.,without oxygen.
Reason: In the primitive atmosphere,oxygen was involved in forming ozone.

Assertion: We have lost all the direct evidence of the origin of life.
Reason: The persons responsible for protecting evidences were not skilled.

The first organisms to evolve on Earth were-

Who proposed the most modern theory regarding the origin of life?