Simple one-celled cyanobacteria-like organisms appeared on Earth:

Two statements regarding the origin of life are given below:
$(a)$ The first organisms that emerged on Earth are believed to have been devoid of chlorophyll and incapable of respiration.
$(b)$ The first food-producing organisms were chemosynthetic and never released oxygen.
Based on the above statements,which of the following options is correct?

Which of the following was not present in free form at the time of the origin of life?

The swan-necked flask experiment was performed by ...........

Choose the correct option in terms of evolution.

Assertion: The earliest organisms that appeared on the earth were non-green and presumably anaerobes.
Reason: The first autotrophic organisms were the chemoautotrophs that never released oxygen.