I'm pretty sure it's the last option because after the electron transport chain, there is actually oxidative phosphorylation which yields 34 ATPs, so the last one is the one that correlates the most.
Mantle convention, convection cells in the mantle, and produces horizontal motion of mantle material close to the Earth surface.
Answer and Explanation:
In H2O molecules, due to formation of intermolecular hydrogen bonds, there is molecular association. Large amount of energy is required to break these intermolecular hydrogen bonds. Intermolecular hydrogen bonding is not possible in H2S. Hence, its boiling point is lower and is a gas.