Question

how life began origins nova neil degrasse tyson hd
the film presents several environments where life might have originated (tide pools, deep - sea vents, caves). which reasoning best explains why deep - sea vents are a strong candidate?
they resemble environments on dry land today
they contain stable temperatures and energy - rich chemical gradients
they prevent all chemical reactions due to pressure
they provide sunlight and constant oxygen flow

Explanation:

Deep - sea vents have stable temperatures and energy - rich chemical gradients. Stable temperatures are important for the stability of molecules and the occurrence of chemical reactions that could lead to the formation of life. Energy - rich chemical gradients provide the necessary energy for the synthesis of complex organic molecules.

They do not resemble dry - land environments (which are very different from deep - sea vent environments). They do not prevent chemical reactions (in fact, chemical reactions occur at deep - sea vents). And they do not provide sunlight (as they are deep in the ocean, far from the reach of sunlight).

Answer:

They contain stable temperatures and energy - rich chemical gradients.