In New York City, a basketball league was devised to create friendship between groups of young black boys and young Jewish boys. Because these kids all had to work together to create friendly competition and a fun environment, the prejudices that existed between the two groups slowly started to fade away. This is an example of the effect?

Mere exposure.

Explanation:

A mere-exposure is a phenomenon in which people tend to like things with which they are familiar. This effect is also known as the familiarity effect. The earliest possible research on this effect is likely to be made by Gustav Fechner.

In the given case, the grown friendship between the two prejudiced groups became possible because of the mere exposure effect. Once these two groups started becoming familiar with each other they developed a good friendship.

So, the correct answer is mere exposure effect.

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explanation:

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