The conditioned stimulus that we have here would be the use of cake as a way to get Sarah to get in a state where her diaper is able to be changed.
This is the term that is used to refer to a stimulus that is triggering that has the ability of being able to get a particular responses from a person. That is, it is one that has the ability of causing a person to act in a certain way.
The conditioned stimulus that we have in the question was done through the use of cake. Sarah has already been said to be a lover of cake. We can see how this was used to condition her to act in a way that her diaper would be able to be changed.
Her mother used the cake piece and the music as a way of soothing her child. Hence we would say that the conditioned stimulus that we have in this question would be the use of cake.
Read more on conditioned stimulus here: https://brainly.com/question/15874680
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