Stimulus equivalence occurs when:

A. Stimuli are equal in attribute or magnitude
B. A response is correctly displayed only under certain circumstances
C. A response is correctly displayed in the presence of a stimulus that has not been trained or reinforced
D. A response is correctly displayed under situations in which the learner has been trained

C. A response is correctly displayed in the presence of a stimulus that has not been trained or reinforced

Explanation:

A Stimulus equivalence is a condition in which the two or more stimuli give the same responses and can show or exhibit the relativity or the symmetry and transitivity and thus occurs in responses that are displayed in the presence of the stimulus that has not been trained and reinforced. It appears to be a technique that mostly used in the case of the teachings and begins with the reading skills and other verbally learned behavior which are a by-product of the interaction.

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