Two motorcyclist racing on an inclined track .
It is impossible that the only vehicle that anyone who is visible has ever driven is a car or SUV .
It is impossible that the only vehicle that anyone who is visible has ever driven is a car or SUV .
It is probable that the only vehicle that anyone who is visible has ever driven is a car or SUV .
The only vehicle that anyone who is visible has ever driven is a car or SUV .