Amaterial through which a current does not move easily is a(n)

A material through which a current does not move easily is called
an insulator.

Technically, charges CAN move through an insulator, but they lose
a lot of energy doing it, so the current that flows through the insulator
is very very small, usually too small to even measure.

Another way to look at it:  Insulators have high resistance.

A., d., and f i think