After Learning About Pavlov in Class, Wendy Wanted to Condition

After learning about Pavlov in class, Wendy wanted to condition her own dog, Beelzebub, to salivate at the sound of a bell. Which of the following would be the most effective method for Wendy to use to produce a strong conditioned response in Beelzebub?

A) Present the bell and the food at the same time.
B) Present the bell and then after it stops ringing, present the food.
C) Present the bell first, and then present the food while the bell is still ringing.
D) Present the food and then, after the food is eaten, present the bell.