If you aunt is staying in a very unhappy marriage due to her investing 15 years in her partner, the problematic decision-making process she is using is the sunk-cost fallacy. (Option D)
Decision-making, in psychology, refers to the cognitive process which results in the selection of a course of action from the several potential alternative options. The resultant action could be either rational or irrational. The decision-making process used in the given scenario is a sunk-cost fallacy. Sunk-cost fallacy refers to the phenomenon in which an individual is unwilling to give up a course of action or strategy as they have heavily invested in it, even though it is evident that relinquishment would be more beneficial.
Note: The question is missing options which are a. the framing effect. b. the conjunction fallacy. c. the availability heuristic. d. the sunk-cost fallacy.
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