The end product of oxidative phosphorylation is

Options

A. NADH
B. Oxygen
C. ADP
D. `ATP + H_(2)O`

Explanation

**Step-by-Step Solution:**

1. **Understanding Oxidative Phosphorylation**:
- Oxidative phosphorylation is a metabolic pathway that occurs in the mitochondria of cells. It involves the oxidation of metabolites and the production of ATP.

2. **Role of Electron Donors**:
- The process starts with electron donors such as NADH and FADH2. These molecules donate electrons to the electron transport chain.

3. **Electron Transfer**:
- The electrons are transferred through a series of proteins in the electron transport chain. This transfer releases energy, which is used to pump protons (H+) across the mitochondrial membrane.

4. **Proton Pumping**:
- The pumping of protons creates a proton gradient across the membrane. This gradient is essential for ATP synthesis.

5. **Splitting of Oxygen**:
- At the end of the electron transport chain, oxygen acts as the final electron acceptor. It combines with the electrons and protons to form water.

6. **Formation of ATP**:
- The energy stored in the proton gradient is used by ATP synthase to convert ADP and inorganic phosphate (Pi) into ATP.

7. **End Products**:
- The main end products of oxidative phosphorylation are ATP and water.

**Final Answer**: The end products of oxidative phosphorylation are ATP and water.

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