Which complex accepts electrons from plastoquinone after it releases H+ ions?

The correct answer is the Cytochrome b6f complex. In the process of photosynthesis, specifically during the light-dependent reactions, plastoquinone (PQ) plays a key role as an electron carrier. After it accepts electrons from photosystem II, plastoquinone becomes reduced and subsequently releases these electrons to the Cytochrome b6f complex.

As plastoquinone donates electrons to this complex, it facilitates the movement of protons (H+ ions) from the stroma into the thylakoid lumen, contributing to the proton gradient that is essential for ATP synthesis. The Cytochrome b6f complex is crucial for linking the two photosystems in the light reactions and also plays a significant role in the electron transport chain.

Other choices involve components that serve different functions in the photosynthetic process. NADP is the final electron acceptor in the chain but does not accept electrons directly from plastoquinone. ATP synthase utilizes the proton gradient established by the Cytochrome b6f complex to synthesize ATP but does not accept electrons. Photosystem I is involved in accepting electrons from the electron transport chain, but it does not interact directly with plastoquinone.

Thus, the Cytochrome