In photosynthesis, electrons that travel through the electron transport chain in the thylakoid membrane come from . in cellular respiration, molecules of supply some of the electrons that travel through the electron transport chain.

In photosynthesis, the electrons that travel through the electron transport chain in the thylakoid membrane comes from water. In the process of cellular respiration, the molecules of NADH donates some of the electrons, which passes through the electron transport chain.

Explanation:

Water supply the initial electron in photosynthesis. The procedure of photolysis dissociates the water into oxygen and hydrogen and discharges electrons that are taken up by photosystem II. In the last step of cellular respiration, that is, oxidative phosphorylation, the donation of electrons is done by NADH that is used to pump ions of hydrogen against the gradient into the mitochondria's inner-membrane space. These flow back of the ions of hydrogen helps in the generation of the energy currency of the cell, that is, ATP.

the correct answer is b