A. The wire is coated with a insulator to prevent shock. B. The birds are natural insulators.C. The birds are not touching the wire. D. The bird's feet are insulators.
It is most definitely A from a physics perspective, because the wires are surrounded by the black coating which acts as the insulator
the birds are not earthed
None of the above answers are correct. The reason the bird doesn't get shocked is that the electricity flow has not be earthed. The wires have insulators on the poles to stop the power being earthed by the poles, which would kill animals or people who touch them. So the power lines are not earthed.
Actually, none of your selections are correct. Birds can sit on a single wire and not get shocked(so can humans) If the bird touches more than one wire, it becomes toast. Something has to be grounded or a complete circuit has to happen for electricity to pass through something. You can't make a light bulb light only touching one end of a battery
