In a DC circuit, which component opposes current flow?

• A. An ideal voltage source
• B. An ideal wire (zero resistance)
• C. A resistor
• D. A capacitor at steady-state DC (after it is fully charged)

Answer: (C)

Verified step by step guidance

1. Understand that in a DC circuit, current flow is influenced by components that provide resistance or opposition to the flow of charge.
2. Recall that an ideal voltage source provides a fixed voltage and does not oppose current; it actually drives current through the circuit.
3. Recognize that an ideal wire has zero resistance, so it does not oppose current flow at all.
4. Know that a resistor is a component specifically designed to oppose current flow by providing resistance, which converts electrical energy into heat.
5. Consider that a capacitor at steady-state DC acts like an open circuit (no current flows through it), so it effectively blocks current rather than opposing it like a resistor does.