Which of the following has the maximum resistance?

Options

A. Voltmeter
B. Milivoltmeter
C. Ammeter
D. Milimmeter

Answer

To determine which of the given options has the maximum resistance, we need to analyze the characteristics of each device mentioned: voltmeter, ammeter, millivoltmeter, and millimeter.

### Step-by-step Solution:

1. **Understanding the Function of Each Device**:
- **Voltmeter**: A voltmeter is used to measure the potential difference (voltage) across two points in a circuit. Ideally, it should have infinite resistance to ensure that it draws minimal current from the circuit, thereby not affecting the measurement.
- **Ammeter**: An ammeter measures the current flowing through a circuit. It is designed to have very low resistance (ideally zero) to allow maximum current to flow through it without affecting the circuit.
- **Millivoltmeter**: A millivoltmeter is a sensitive device used to measure small voltages (in millivolts). It is designed to have a high resistance, even higher than that of a standard voltmeter, to minimize the current drawn from the circuit.
- **Millimeter**: This term seems to be a misnomer in this context. If it refers to a measuring device, it is not relevant to resistance measurements in electrical circuits.

2. **Comparing Resistances**:
- **Resistance of Voltmeter**: High (ideally infinite)
- **Resistance of Ammeter**: Low (ideally zero)
- **Resistance of Millivoltmeter**: Higher than that of a voltmeter
- **Resistance of Millimeter**: Not applicable

3. **Conclusion**:
- Among the devices listed, the millivoltmeter has the highest resistance, as it is designed to measure very small voltages while drawing minimal current, even more so than a standard voltmeter.

### Final Answer:
The device with the maximum resistance is the **millivoltmeter**.

---