I am confused between C and D but I will go with C.
I would have been more confident about C, if it had stated that the dog associated his food with the ringing of a bell.

Waiting for the OA.

In the first line, when a dog smells food, he salivates. In the next step, a bell is rung whenever food is given to the dog. After repeating this the experiment a few times, a dog salivates even when he hears a bell because he associates the sound of the bell with the food. Clearly, option C is the answer.

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Breakdown the argument:
In a famous experiment by Pavlov, when a dog smelled foof, it salivated. Subsequently, a bell was rung whenever food was placed near the dog. After a number of trials, only the bell was rung, where upon the dog would salivate even though no food was present.

Dog---smell->Food --->salivated
|
(Bell)

Inference?

A. Dogs are easily fooled.
Too far
B. Dogs are motivated only by the sound of a bell.
motivation is not equal to salvation.
C. The ringing of a bell was associated with food.
That was dog perceived
D. A conclusion can not be reached on the basis of one experiment.
Generic.
E. Two stimuli are stronger than one.
It doesn't say it

Answer C

Since this is a draw a conclusion type question we can only use data from the question stem to pick our options. No additional data can be used
Here when trying to determine the conclusion drawn by the author, we need to put ourselves in his shoes.
Option A : No clear evidence of the author assuming the same. Wrong
Option B : No mention of the dog being motivated by food/bell. Wrong
Option C : Food being placed caused salivation, subsequently ( at the same time) the bell was also rung. Meaning the food being placed and the ringing of the bell happens at the same time Let's keep this option
Option D : Clearly Wrong, Author seems to have a conclusion as per the stem
Option E: Not mentioned in stem

Clearly option C is our winner

Is this really GMAT question? I voted for C. What is a source?
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