Kirchhoff's Current Law for balanced circuits

Steps:

• In a correctly working cooker, current flows from the live wire to power the appliance.
• The same current returns through the neutral wire to complete the circuit.
• The earth wire provides a safety path but carries no current under normal operation.
• Thus, live and neutral currents are equal, while earth current is zero.

Why D is correct:

• Kirchhoff's Current Law states that total current entering a junction equals total current leaving; in a balanced load, live input matches neutral output.

Why the others are wrong:

• A: Earth carries no current normally, so currents are not equal in all three.
• B: Earth has zero current, unlike the neutral's full load current.
• C: Earth has zero current, unlike the live's full load current.

Final answer: D