Prejudice can be not only subtle but also automatic and unconscious. this is best illustrated in studies of

The answer that best completes the statement above is this: IMPLICIT ATTITUDES. Basically, when we say implicit attitudes, these are the attitudes presented without conscious awareness, or unconsciously towards the self and others. In this study, the attitudes can either be favorable or not. When we say prejudice, this is an opinion made about something or someone without any factual or proven facts and is often biased. 

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