One of the defining characteristics of implicit memory is that a. it is enhanced by the self-reference effect. b. people are not conscious they are using it. c. people use it strategically to enhance memory for events. d. it always leads to episodic memory for events.

b. people are not conscious they are using it.          

Explanation:

Implicit memory: In psychology, the term "implicit memory" is also referred as automatic memory or unconscious memory and is described as one of the different memories that tend to used past experiences in order to remember various things in the absence of being thinking about the same thing. However, the performance related to the implicit memory of an individual via previous experiences of an individual, no matter the time those experiences occurred in his or her life.

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