Three of these pairs of quantities are related by direct variation. Which pair is NOT?
A - x = hours traveled at 60 miles per hour, and y = total distance traveled
B - x = length of a rectangular table, in inches, and y = length of the table, in centimeters
C - x = number of $1-off coupons used, and y = amount saved
D - x = time it takes to travel 60 miles, and y = speed traveled