Photosystem II occurs in

Options

A. cytochrome
B. stroma
C. grana thylakoids
D. mitochondrial surface

Explanation

To answer the question "Photosystem II occurs in," we can follow these steps:

### Step-by-Step Solution:

1. **Understand Photosystems**: Photosynthesis involves two main photosystems, Photosystem I (PS I) and Photosystem II (PS II). Both are essential for the light-dependent reactions of photosynthesis.

2. **Identify Locations**:
- Photosystem I (PS I) is found in the stromal thylakoids and the non-appressed parts of the granal thylakoids.
- Photosystem II (PS II) is specifically located in the appressed parts of the granal thylakoids.

3. **Analyze the Options**:
- A. Cytochrome: This is not a location for Photosystem II.
- B. Stroma: While related to the overall process of photosynthesis, it is not where PS II is located.
- C. Granithelochoids: This option refers to the appressed parts of the granal thylakoids where Photosystem II is found.
- D. Mitochondrial surface: This is not related to photosynthesis and does not contain Photosystem II.

4. **Select the Correct Answer**: Based on the information, Photosystem II occurs in the granal thylakoids, specifically in the appressed regions. Therefore, the correct answer is **C. Granithelochoids**.

### Final Answer:
Photosystem II occurs in **C. Granithelochoids**.

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