Effie no longer eats egg salad sandwiches—some time ago, she found herself vomiting after consuming a sandwich that probably had spoiled mayonnaise in it. which pairing correctly identifies the stimulus in this situation?

Vomiting due to spoiled mayonnaise acts as stimulus

Explanation:

Stimulus means a thing that provokes a certain reaction. As eating sandwich with spoiled mayo caused Effie to vomit that in turn caused her to avoid eating egg salad sandwiches, therefore vomit due to spoiled mayonnaise acts as stimulus.

Unconditioned stimulus - bacteria

Explanation:

According to a different source, these are the options that come with this question:

In this example, the unconditioned stimulus would be bacteria. An unconditioned stimulus is one that unconditionally, and naturally, triggers a response. An unconditioned stimulus leads to an unconditiond response. In this example, the response is that Effie is no longer able to consume egg salad sandwiches.

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