Answer
(b)
Work Step by Step
Choose $A$ to refer to the action "The car has gas", and $B$ to refer to the action "it will run". Now, we have the implication $A\Longrightarrow B$. So its contrapositive is $\neg B\Longrightarrow \neg A$. Therefore, the right answer is:
(b) If the car will not run, then it has no gas.