Which of the following is a part of cytochrome?

Options

A. Mg
B. Zn
C. Fe
D. Ca

Answer

### Step-by-Step Solution:

1. **Understand what Cytochrome is**: Cytochrome is a type of protein that plays a crucial role in the electron transport chain and redox reactions within cells.

2. **Identify the components of Cytochrome**: Cytochromes contain a specific component known as a heme group. This heme group is essential for the function of cytochromes.

3. **Recognize the role of Iron**: The heme group within cytochromes contains iron as its central cofactor. This iron is vital for the electron transfer processes that cytochromes facilitate.

4. **Evaluate the options provided**: The question asks which of the given options is a part of cytochrome. Since we know that iron is a component of the heme group in cytochromes, we can conclude that iron is the correct answer.

5. **Conclude the answer**: Therefore, the correct answer to the question "Which of the following is a part of cytochrome?" is **Iron**.