Wires `P` and `Q` have the same resistance at ordinary (room) temperature. When heated, resistance of `P` increases and that of `Q` decreases. We conclude that

Options

A. P and Q are conductors of different materials
B. P is n-type semiconductor and Q is p-type semiconductor
C. P is semiconductor and Q is conductor
D. P is conductor and Q is semiconductor

Answer

To solve the question, we need to analyze the behavior of the resistances of wires P and Q when subjected to an increase in temperature.

### Step-by-Step Solution:

1. **Understanding the Resistance Behavior**:
- At room temperature, both wires P and Q have the same resistance.
- When the temperature increases, the resistance of wire P increases, while the resistance of wire Q decreases.

2. **Identifying the Type of Materials**:
- **Conductor**: Typically, conductors (like metals) have a positive temperature coefficient of resistance. This means that as the temperature increases, the resistance also increases.
- **Semiconductor**: Semiconductors have a negative temperature coefficient of resistance. This means that as the temperature increases, the resistance decreases.

3. **Analyzing Wire P**:
- Since the resistance of wire P increases with temperature, we can conclude that wire P behaves like a conductor.

4. **Analyzing Wire Q**:
- Since the resistance of wire Q decreases with temperature, we can conclude that wire Q behaves like a semiconductor.

5. **Conclusion**:
- From the observations above, we conclude that wire P is a conductor and wire Q is a semiconductor.

### Final Conclusion:
- Wire P is a conductor (positive temperature coefficient) and wire Q is a semiconductor (negative temperature coefficient).