The answer would be B because you can go and find evidence and facts to conduct an investigation on that.
Such ions are said to be isoelectronic
6:12:6: - this simplifies to 1:2:1 (answer)
You get the simplest form by dividing each of the 3 numbers by 6.
It’s C magnetic field because with the forces of the magnets pushing against each other it gets the engine to start turning the wheels.
