Which of the following does not represent a proportional relationship?



A. Zoe earns a base salary of $500 plus 3% commission


B. Dane drove 200 miles at a consistent speed for four hours


C. Water leaks from the faucet at a rate of 1/2 of a liter per hour


D. A recipe for biscuits calls for 3 cups of flour and 1 1/2 teaspoons of baking soda