Answer
Answer Choice $H$
Work Step by Step
Look at the function.
$g = 0.05d$
It looks like g is dependent on the value of d. Check this with the real life scenario.
"The amount of money needed for gasoline is dependent on how many miles he travels"
This seems plausible. Let's try the opposite situation.
"The number of miles he travels is dependent on the amount of money needed for gasoline."
This doesn't seem right. The first situation is most reasonable. Answer Choice $H$ matches the situation.