The theory of Oparin is based on which of the following?

The first organisms to appear on Earth were more like plants because:

Following are the two statements regarding the origin of life.
$(A)$ The earliest organisms that appeared on the earth were non-green and presumably anaerobes.
$(B)$ The first autotrophic organisms were the chemoautotrophs that never released oxygen.
Of the above statements,which one of the following options is correct?

The first cell produced on Earth is:

Which one of the following experiments suggests that the simplest living organisms could not have originated spontaneously from non-living matter?

In which era was there no life?