Assertion : 1. In the presence of an electric field, the canal rays are deflected towards the negative electrode.
Reason : Canal rays are composed of electrons which are negatively charged.

Options

A. If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
B. If both Assertion and Reason are correct and Reason is not the correct explanation of Assertion.
C. If Assertion is correct but Reason is incorrect.
D. If Assertion is incorrect but Reason is correct.

Answer

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

### Step 1: Understanding the Assertion
The assertion states: "In the presence of an electric field, the canal rays are deflected towards the negative electrode."

- **Canal Rays**: Canal rays, also known as positive rays, are streams of positively charged particles (usually protons or ions) that travel in a vacuum tube.
- **Electric Field Effect**: In an electric field, positively charged particles are attracted to the negative electrode. Therefore, the assertion is correct.

### Step 2: Understanding the Reason
The reason states: "Canal rays are composed of electrons which are negatively charged."

- **Composition of Canal Rays**: This statement is incorrect because canal rays are not composed of electrons; they are made up of positively charged particles. Electrons are negatively charged and are not the constituents of canal rays.
- Since the reason is incorrect, it does not explain the assertion.

### Step 3: Conclusion
- The assertion is correct: Canal rays are deflected towards the negative electrode due to their positive charge.
- The reason is incorrect: Canal rays are not composed of electrons.

### Final Answer
- The assertion is true, but the reason is false. Therefore, the correct conclusion is that the assertion is correct, but the reason is not a correct explanation for the assertion.

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