Jack Regularly Feeds His Neighbor's Dog,Oscar

Jack regularly feeds his neighbor's dog,Oscar.He announces his arrival by ringing his bicycle bell and feeds Oscar mouth-watering treats.As Jack has been doing this for two weeks,every time he hears Jack's bicycle bell,Oscar begins salivating with the expectation of being fed.In this scenario,Oscar learns the response to the bicycle bell through _____.

A) classical conditioning
B) operant conditioning
C) insight learning
D) modeling