Question

When there is a difference in voltage, the flow of charge is called which of the following

Answer 1

You did not list "the following"
But, normally the flow of charge is termed "current"
Professors usually refer to positive charge while the military schools and most layman refer to current as the flow of electrons (negative charge) consequently we have what is termed the "conventional" flow and the electron flow which flow in opposite directions. Regardless, electron flow is in a direction towards the most positive potential.