Assertion : Purple cabbage leaves do not lose their colour in cold water but do so in boiling water.
Reason : Plasma membrane becomes impermeable in boiling water and pigments come out.

Options

A. If both Assertion and Reason are true and Reason is correct explanation of Assertions.
B. If both Assertion and Reason are true but Reason is not correct explanation of Assertion.
C. If Assertion is true but Reason is false.
D. If both Assertion and Reason are false.

Answer

To analyze the given assertion and reason, we will break down the statements step by step.

### Step 1: Understanding the Assertion
The assertion states that "Purple cabbage leaves do not lose their color in cold water but do so in boiling water."
- This means that when purple cabbage leaves are placed in cold water, they retain their color. However, when placed in boiling water, they lose their color.

### Step 2: Understanding the Reason
The reason provided is "Plasma membrane becomes impermeable in boiling water and pigments come out."
- This suggests that the plasma membrane of the cabbage leaves becomes impermeable when exposed to boiling water, which leads to the release of pigments from the leaves.

### Step 3: Evaluating the Assertion
- The assertion is true. Purple cabbage contains anthocyanin pigments that are stable at lower temperatures (cold water) but can be released when the plant cells are subjected to high temperatures (boiling water).

### Step 4: Evaluating the Reason
- The reason is false. The plasma membrane does not become impermeable in boiling water; instead, it becomes damaged or denatured, which allows the pigments to leak out. The correct term would be that the plasma membrane becomes more permeable or loses its integrity, leading to the release of pigments.

### Step 5: Conclusion
- Since the assertion is true and the reason is false, the correct answer to the question is that the assertion is true but the reason is false.

### Final Answer
The correct option is: **Assertion is true, but reason is false.**

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