A Certain Sample Carries a Current of 4 a When $\Omega$

Multiple Choice

A certain sample carries a current of 4 A when the potential difference is 2 V and a current of 10 A when the potential difference is 4 V. This sample:

A) obeys Ohm's law
B) has a resistance of 0.5 $\Omega$ at 1 V
C) has a resistance of 2.5 $\Omega$ at 2 V
D) has a resistance of 25 $\Omega$ at 2 V
E) does not have a resistance