A vaccine can help keep people healthy and protect them from a certain virus. For example people in the United States get the flu shot when they get this shot the vaccine wont magically get rid of the virus but rather help them fight it off and protect them in the future if they keep up to date getting the vaccine
The correct answer is proteins.
The oxidative phosphorylation in the eukaryotes takes place within the mitochondria with the help of electron transport chain. The main objective of the electron transport chain is to accumulate enough amount of protons in the intermembrane space so that there will be a concentration gradient which would help in the production of ATP.
The electron transport chain comprises of various molecules, but majorly the proteins, which are situated in the inner membrane of the mitochondria.
I’m assuming you mean if the sun dies out. If so, then most things on earth would die within a few days due to lack of photosynthesis and to freezing temperatures (which is what would cause humans to die).