I’m not sure to be honest
Answer:
The last one is correct punctuation.
It would be it is a primary subject in the story that helps understand the hidden motives of the main character.
Scientists had suspected that our planet formed dry, with high-energy impacts creating a molten surface on the infant Earth<span>. </span>Water came<span> much later, went the thinking, thanks to collisions with wet comets and asteroids.</span>
