If the weight of the car were the dependent variable, then
that would mean that the weight of the car depends on the
gas mileage. In that case, the car would probably have
different weights in the city and on the open highway.
The car would really get heavy when you drive it during
rush hour on a rainy day. But if a trained professional
efficiency driver checked the tire pressure, tuned up the
\ignition system and the fuel mixture, then got in and took it
for a spin out on the highway on a cool sunny day, maintained
a constant speed, avoided sudden starts and stops, let the
car gain speed on the down-hills and let it lose speed on the
up-hills, then the car's weight would drop lower than it's ever
been before.
Does any of this sound reasonable to you ?
Go ahead and take a wild guess.
Then mark ' A ' .