Assertion: Faraday's laws are consequences of conservation of energy.
Reason: In a purely resistive `AC` circuit, the current lags behind the e.m.f. in phase

Options

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

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Faraday's laws are consequences of conservation of energy."
- Faraday's laws of electromagnetic induction explain how a change in magnetic flux through a circuit induces an electromotive force (emf) in that circuit. This process involves the conversion of mechanical energy into electrical energy.
- Since energy cannot be created or destroyed (according to the law of conservation of energy), the energy used to induce the current must come from the mechanical energy applied to change the magnetic flux. Therefore, this assertion is **true**.

2. **Understanding the Reason**:
- The reason states that "In a purely resistive AC circuit, the current lags behind the e.m.f. in phase."
- In a purely resistive AC circuit, the relationship between voltage (V) and current (I) is given by Ohm's law: V = IR. In this case, both the voltage and current are in phase, meaning they reach their maximum and minimum values at the same time.
- Therefore, in a purely resistive circuit, the current does not lag behind the emf; instead, they are in phase. This makes the reason **false**.

3. **Conclusion**:
- Since the assertion is true and the reason is false, we conclude that the correct answer is that the assertion is true, but the reason is false.

### Final Answer:
- The assertion is true, and the reason is false.