A : High voltage ( high tension ) supply must have very large internal resistance.
R: If the circuit is accidentally shorted , then the current drawn will not exceed safely limits if internal resistance is high.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion , then mark
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion then mark.
C. If Assertion is ture statement but Reason is false , then mark
D. If both Assertion and Reason are false statements then mark.

Answer

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

### Step-by-Step Solution:

1. **Understanding Assertion (A)**:
- The assertion states that a high voltage (high tension) supply must have a very large internal resistance.
- This is true because high voltage supplies can produce very high currents if not properly controlled.

**Hint**: Consider the relationship between voltage, current, and resistance as described by Ohm's Law.

2. **Understanding Reason (R)**:
- The reason states that if the circuit is accidentally shorted, then the current drawn will not exceed safe limits if the internal resistance is high.
- This is also true. In the event of a short circuit, a high internal resistance limits the current flow, preventing it from exceeding safety limits.

**Hint**: Think about what happens to current when resistance is increased in a circuit with a constant voltage.

3. **Analyzing the Relationship**:
- According to Ohm's Law, \( I = \frac{V}{R} \). If the voltage (V) is high and the internal resistance (R) is also high, the current (I) can be kept at a safe level.
- If the internal resistance is low, a short circuit could lead to an extremely high current, which can be dangerous and cause damage.

**Hint**: Reflect on how increasing resistance affects current flow in a circuit.

4. **Conclusion**:
- Both the assertion and the reason are correct, and the reason correctly explains why the assertion is true.
- Therefore, the answer to the question is that both statements are true, and the reason is a valid explanation for the assertion.

**Hint**: Consider how the safety of electrical systems is maintained through design choices like internal resistance.

### Final Answer:
Both the assertion (A) and the reason (R) are correct, and the reason correctly explains the assertion.