What colour is "earth wire" in domestic wiring?

 In an electrical circuit, the green wire represents earthing or grounding.

Circuits or other equipment are shielded from electric shock by earthing. It does this by giving a fault current a way (a protective conductor) to get to earth.

Green wires are mostly utilised in socket applications. AC, a geyser, a TV, a microwave, etc.

Neutral and phase are the only two wires that switches typically have.

Green is the right response.