(A): A dynamo converts mechanical energy into electrical energy.
(R): The dynamo is based on the principle of electromagnetic induction.

Options

A. Both .A. and .R. are true and .R. is the correct explanation of .A.
B. Both .A. and .R. are true and .R. is not the correct explanation of .A.
C. .A. is true and .R. is false
D. .A. is false and .R. is true

Answer

To solve the question, we need to analyze both statements: the assertion (A) and the reason (R).

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that "A dynamo converts mechanical energy into electrical energy."
- This statement is true. A dynamo is indeed a type of electrical generator that transforms mechanical energy (usually from a rotating motion) into electrical energy.

2. **Understanding the Reason (R)**:
- The reason states that "The dynamo is based on the principle of electromagnetic induction."
- This statement is also true. The functioning of a dynamo relies on electromagnetic induction, which occurs when a conductor (like a coil) is moved through a magnetic field, inducing an electromotive force (EMF).

3. **Analyzing the Relationship**:
- We need to determine if the reason (R) correctly explains the assertion (A).
- Since the dynamo operates on the principle of electromagnetic induction to convert mechanical energy into electrical energy, the reason does indeed provide a correct explanation for the assertion.

4. **Conclusion**:
- Both the assertion and the reason are true, and the reason is the correct explanation of the assertion.
- Therefore, the answer is: **Both A and R are true, and R is the correct explanation of A.**

### Final Answer:
Both A and R are true, and R is the correct explanation of A.

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