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In a laboratory setting, people viewed simple visual stimuli and chose the categories to which they belonged. A computer tracked people's choices, confidence ratings, and response times (RTs) when either all alternatives available for a choice were reasonable or one alternative was very unlikely. While the objective probability of an alternative in a set being correct decreases with the introduction of another alternative, I expected that inclusion of an implausible alternative would increase confidence that the alternative chosen was correct. I further suspected that RT would be constant despite changes in the types of alternatives available. Accuracy, confidence, and RT were predominantly unchanged by manipulating alternatives in the choice set. This contradicted two of my hypotheses and the hypotheses of other investigators in this area of research. A final experiment focusing just on confidence obtained more contradictory results, suggesting that people process all combinations of alternatives in a set similarly.