At the time of short-circuit, the current in the circuit:
(a) reduces substantially.
(b) does not change.
(c) increases heavily.
(d) vary continuously.

Options

A. reduces substantially
B. does not change
C. increases heavily
D. vary continuously

Answer

To solve the question about the behavior of current during a short circuit, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Short Circuit**:
- A short circuit occurs when there is an unintended path in the circuit that allows current to flow with very low resistance. This can happen due to faulty wiring or damaged components.

2. **Resistance in the Circuit**:
- In a normal circuit, the current is determined by Ohm's Law, which states that \( I = \frac{V}{R} \), where \( I \) is the current, \( V \) is the voltage, and \( R \) is the resistance.
- During a short circuit, the resistance \( R \) becomes very low.

3. **Effect of Low Resistance on Current**:
- Since resistance is inversely proportional to the current, when the resistance decreases significantly, the current increases substantially.
- Therefore, if the resistance approaches zero, the current can increase to very high levels, potentially leading to dangerous situations like overheating or fires.

4. **Conclusion**:
- Based on the above reasoning, we can conclude that at the time of a short circuit, the current in the circuit increases heavily.

### Final Answer:
(c) increases heavily.

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