Vernon is an active, friendly baby. he receives more social stimulation from his parents than vivian, who is a passive, quiet infant. this is an example of a(n) gene–environment correlation.

The correct answer is an evocative gene-environment correlation. 

An evocative gene-environment correlation refers to the phenomenon where the behavior that an individual has inherited elicits or leads to an environmental response. In this instance, Vernon's (inherited) temperament is active and friendly due to which his parents provide him with social stimulation. On the other hand, Vivian, who has a more passive and quiet nature (inherited) receives less stimulation from her parents. 

This is an example of "Evocative gene-environment correlation".

Evocative gene-environment correlation happens when a person's (heritable) conduct inspires a natural reaction. For instance, the relationship between conjugal clash and gloom may mirror the strains that emerge while connecting with a discouraged life partner as opposed to a causal impact of conjugal clash on chance for wretchedness. 

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