What is the relationship between voltage and current (assuming the resistance stays the same)?

a
Voltage does not affect current
b
If the voltage decreases, the current increases
c
If the voltage increases, the current increases

c. If the voltage increases, the current increases (assuming the resistance stays the same, according to Ohm's law, V=IR, where V is voltage, I is current, and R is resistance). Conversely, if the voltage decreases, the current decreases.