Site of Krebs' cycle in mitochondria is

Options

A. outer membrane
B. matrix
C. oxysomes
D. inner membrane.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the specific site within the mitochondria where the Krebs cycle occurs. The Krebs cycle is also known as the TCA (tricarboxylic acid) cycle.

2. **Structure of Mitochondria**: Mitochondria have a unique structure consisting of two membranes: an outer membrane and an inner membrane. The inner membrane is folded into structures called cristae, and the space enclosed by the inner membrane is known as the matrix.

3. **Identifying the Site of the Krebs Cycle**: The Krebs cycle takes place in the matrix of the mitochondria. This is the area where various biochemical reactions occur, including those involved in aerobic respiration.

4. **Conclusion**: Based on the structure of the mitochondria and the location of the Krebs cycle, the correct answer is **option B: matrix**.

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