What is a characteristic of universal affirmative statements?

Universal affirmative statements are defined by their ability to make a positive claim about every member of a given category. This means that when a statement is framed as a universal affirmative, it asserts that all subjects within a particular category possess a certain attribute or characteristic. For instance, the statement "All birds can fly" is a universal affirmative because it applies to every member of the category "birds" by claiming that they all share the ability to fly (although some exceptions exist).

The other options do not accurately describe universal affirmative statements. For instance, asserting that they apply only to some members would classify them as particular affirmatives instead. Negative claims contradict the essence of what a universal affirmative is, as they would suggest the absence of a quality among members of a category rather than affirming it. Finally, relating to no specific category does not align with the definition of universal affirmatives, which inherently require a category to apply to. Thus, the defining characteristic of universal affirmative statements is their positive claim about every member within a category.