What is a characteristic of a multiple-choice constraint in linear programming?

In the context of linear programming, particularly when dealing with multiple-choice constraints, the characteristic that stands out is that the sum of two or more binary (0-1) variables must equal 1. This scenario applies when a decision-maker has multiple options, but only one can be chosen. The binary variables represent the choices, where each variable corresponds to an option: it takes a value of 1 if that option is selected and 0 if it is not. By imposing the restriction that the sum of these variables equals 1, it ensures that only one of the options can be chosen, reflecting the exclusivity inherent in multiple-choice scenarios.

In contrast, the other potential characteristics listed do not encapsulate the essence of a multiple-choice constraint as effectively. For instance, while limiting the maximum of one binary variable to 1 may seem relevant, it is more accurate to state that the sum of selected vars must equal 1, as this encompasses the entire set of options. The idea that the sum of binary variables must equal 0 is contrary to the purpose of selecting an option. Similarly, the requirement that all variables must be greater than 0 is not applicable in this context, as binary variables are intended to only take 0 or