In Which One of the Following Situations Will the Transaction

In which one of the following situations will the transaction not be binding on the principal?

A) An employee of a flower shop is sent to the flower market every week to make purchases. This week he is told to buy only roses, but he can't pass up a tremendous deal on daisies and purchases a large quantity of them for the store.
B) A real estate salesperson, after disclosing the fact to his client, purchases the house the client is selling for himself.
C) A truck driver who is not an agent (no actual, implied, or apparent authority) enters into a contract on behalf of his employer to sell the cargo of ripe tomatoes after the truck breaks down and he can't get hold of the boss.
D) A chauffeur, going against specific instructions, purchases a new car for his employer. The employer has done nothing to lead the seller to believe the chauffeur has such authority, but is persuaded by the chauffeur to go for a drive before returning the car.
E) A salesman at a men's clothing store has heard a rumor that the store will be going out of business. The boss is out of the store when a customer who has heard the same thing comes in and offers to purchase all of the stock, display cases, and fixtures. The salesman accepts on behalf of the employer.