In a common emitter, unbypassed resister provides

Option A: Voltage shunt feedback is incorrect because voltage shunt feedback involves taking a portion of the output voltage and feeding it back in parallel with the input. This is not what an unbypassed resistor in a common emitter configuration does.

Option B: Current series feedback is incorrect because current series feedback involves taking a portion of the output current and feeding it back in series with the input. This is not characteristic of an unbypassed resistor in a common emitter amplifier.

Option C: Negative voltage feedback is correct because the unbypassed resistor in a common emitter amplifier provides negative voltage feedback. This resistor, typically placed in the emitter leg of the transistor, causes a decrease in the gain by reducing the overall amplification and stabilizing the output, leading to better linearity and reduced distortion.

Option D: Positive current feedback is incorrect because positive current feedback would increase the overall gain and instability, which is not the role of an unbypassed resistor in a common emitter configuration.

Conclusion: The correct answer is Option C: Negative voltage feedback because the unbypassed resistor in a common emitter amplifier provides negative voltage feedback, which stabilizes the gain and reduces distortion in the amplifier.