$ Mitochondria are called "Food-Factories" of a plant cell.
A Plant cell is called as a closed system.

Options

A. If both As and R are correct and R is correct explanation of As
B. If both As and R are correct but R is not correct explanation of As
C. If As is correct, R is wrong
D. If both As and R are wrong.

Answer

To solve the question regarding the assertion and reason about mitochondria and plant cells, we will analyze each statement step by step.

### Step 1: Analyze the Assertion
The assertion states that "mitochondria are called food factories of a plant cell."

**Explanation**:
- Mitochondria are known as the "powerhouses" of the cell, not food factories. Their primary function is to produce ATP (adenosine triphosphate), which is the energy currency of the cell.
- Therefore, this statement is incorrect.

### Step 2: Analyze the Reason
The reason states that "a plant cell is called a closed system."

**Explanation**:
- A closed system is defined as one that cannot exchange matter or energy with its surroundings.
- However, plant cells are actually open systems because they can exchange both matter (like nutrients and gases) and energy (through processes like photosynthesis and respiration) with their environment.
- Thus, this statement is also incorrect.

### Step 3: Conclusion
Since both the assertion and the reason are incorrect, we conclude that the correct answer is option D: both A and R are wrong.

### Final Answer:
Both the assertion and reason are false.

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