How Does the Technique Called Ionophoresis Work

How does the technique called ionophoresis work?

A) Molecules inside a glass pipet can be expelled by pressure.
B) Molecules inside a glass pipet can be expelled by electrical charge.
C) Molecules inside a glass pipet can be expelled by simple diffusion.
D) Molecules inside a glass pipet can be expelled by suction.
E) Molecules inside a glass pipet can be expelled by concentration gradient.