Assertion : A photocell is a technological application of the photoelectric effect.
Reason : Photocell is a device whose electric properties are affected by electricity.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Explanation

To analyze the assertion and reason provided in the question, we can break it down into steps:

### Step 1: Understand the Assertion
The assertion states that "A photocell is a technological application of the photoelectric effect."
- A photocell is indeed a device that operates based on the photoelectric effect, which is the phenomenon where electrons are emitted from a material when it is exposed to light (or electromagnetic radiation). This means that the assertion is true.

### Step 2: Understand the Reason
The reason states that "Photocell is a device whose electric properties are affected by electricity."
- This statement is misleading. A photocell primarily responds to light energy, not electricity. The electric properties of a photocell are influenced by the light that strikes it, which causes the emission of electrons and generates an electric current. Therefore, this reason is false.

### Step 3: Conclusion
Based on the analysis:
- The assertion is true: A photocell does utilize the photoelectric effect.
- The reason is false: The operation of a photocell is not directly affected by electricity but rather by light energy.

### Final Answer
Thus, the correct option is that the assertion is true, but the reason is false.

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