Which of the following is the correct sequence of events in the origin of life? I. formation of protobionts II. synthesis of organic monomers III. synthesis of organic polymers IV. formation of DNA-based genetic systems

II,III, I and IV.

Explanation:

The studies on the origin of life on Earth is supported by more predictions and few experimental proofs.

The experimental proofs like the Miller experiment show that when the conditions of Earth were harsh with high temperature then the atmospheric molecules tried to form bonds and when the temperature went down they formed the monomers.

The reducing environment later combines these monomers and formed the first polymers on the Earth-like the amino acids, nucleotides. The nucleotides combined and formed the RNA which has the ability to self replicate. These molecules gathered and formed the first protobionts. These protobionts later formed the DNA as the evolved structure of the RNA molecule.

Thus, II,III, I and IV is correct.

a- all cells come from pre-existing cells