Which term describes the change in how quickly users can make decisions as the number of options increases?

The term that describes the change in how quickly users can make decisions as the number of options increases is indeed Hick's Law. This principle states that the time it takes for a person to make a decision increases with the number and complexity of choices. Essentially, as the number of options grows, the cognitive load on the user also increases, which can slow down their decision-making process and potentially lead to choice overload.

Hick's Law is vital for UX designers as it emphasizes the importance of simplifying choices to enhance user experience. By limiting the number of options presented to users or organizing choices in a more user-friendly manner, designers can facilitate quicker decision-making, ultimately improving user satisfaction and efficiency.

Other terms in the options refer to different concepts: Fitts' Law pertains to the relationship between the distance and size of a target and the time it takes to reach it, while the Gestalt Principles relate to how people perceive visual elements in relation to one another. Usability heuristics cover broad rules of thumb for interaction design but do not specifically address the influence of choice quantity on decision speed.