Final answer:
Unconscious reasoning is involved in perceptual illusions, the false fame effect, and blindsight, as all these phenomena rely on the brain's ability to process information without our conscious awareness.
Step-by-step explanation:
Unconscious reasoning refers to thought processes that occur without our conscious awareness. In the context of the question, unconscious reasoning is used in all of the above options: a) perceptual illusions, b) the false fame effect, and c) blindsight. Perceptual illusions occur when our brain fills in gaps in the sensory information it receives, creating a perception that differs from reality. The false fame effect is a phenomenon where names that individuals have encountered recently, but unconsciously, are more likely to be recognized as famous in a later test. Blindsight is a condition where individuals with visual cortex damage can respond to visual stimuli that they do not consciously see. All these phenomena involve unconscious processing of information, which affects our perception and cognition.