Final answer:
The mental process behind the conjunction fallacy aids in social interactions by enabling quick inferences and decisions based on rules of thumb, which are necessary for efficient day-to-day functioning and social cohesion.
Step-by-step explanation:
The mental process responsible for the conjunction fallacy is often unchecked by the confirmation bias, where people search for, interpret, favor, and recall information that confirms their pre-existing beliefs. While this can lead to incorrect conclusions, it also aids in social interactions by allowing individuals to make quick inferences and decisions that are necessary for day-to-day functioning and building social cohesion within groups. These mental shortcuts stem from our evolutionary need to make quick and efficient judgments which are crucial for survival, though they can sometimes lead us astray in more complex or novel situations.
In everyday life, the conjunction fallacy, although a cognitive bias, helps with social interactions (Option D). People rely on rules of thumb to guide them, which are quick, mostly unconscious inferences that help us navigate socially complex environments and communicate effectively without overburdening our cognitive processes with constant analysis.