Concept:
Clamper circuits shift the DC level of a waveform.
Step 1: Identify components
Circuit has capacitor, diode, and resistor.
Step 2: Working during positive half cycle
Capacitor charges through diode.
Step 3: During negative half cycle
Capacitor adds voltage to input signal.
Step 4: Output waveform
Entire waveform shifts upward.
Step 5: Conclusion
\[
\boxed{\text{Positive clamper}}
\]
Final Answer:
\[
\boxed{(C)}
\]