Of the following, which is not associated with the mitochondria?

Options

A. ATP production
B. Cristae
C. Stroma
D. Matrix

Explanation

To determine which option is not associated with mitochondria, we will analyze each option provided in the question:

1. **ATP Production**: Mitochondria are known as the "powerhouse of the cell" because they are primarily responsible for producing ATP (adenosine triphosphate), which is the energy currency of the cell. Therefore, ATP production is associated with mitochondria.

2. **Cristae**: Cristae are the folds of the inner membrane of mitochondria. These folds increase the surface area for chemical reactions, particularly those involved in ATP production. Thus, cristae are also associated with mitochondria.

3. **Stroma**: Stroma is a term used to describe the fluid-filled space in chloroplasts where the light-independent reactions of photosynthesis occur. Mitochondria do not have stroma; they have a matrix instead. Therefore, stroma is not associated with mitochondria.

4. **Matrix**: The matrix is the innermost compartment of mitochondria, where various metabolic reactions occur, including the Krebs cycle. Hence, the matrix is associated with mitochondria.

Based on this analysis, the correct answer is **Stroma**, as it is not associated with mitochondria.

### Step-by-Step Solution:
1. Identify the options related to mitochondria: ATP production, cristae, stroma, and matrix.
2. Analyze each option:
- ATP production: Associated with mitochondria.
- Cristae: Associated with mitochondria.
- Stroma: Not associated with mitochondria (found in chloroplasts).
- Matrix: Associated with mitochondria.
3. Conclude that the option that is not associated with mitochondria is **Stroma**.