Final answer:
Artistic ability could not serve as a useful operational definition of interest in art, while the number of art classes taken, time spent in art museums, and the number of art books owned can serve as operational definitions.
Step-by-step explanation:
An operational definition of interest in art refers to a measurable way to define and quantify a person's level of interest in art. Out of the options provided, artistic ability could not serve as a useful operational definition of interest in art.
Artistic ability is a subjective quality that cannot be easily measured or quantified. It involves talent, skill, and creativity, which are not necessarily synonymous with interest in art. A person may have strong artistic ability but may not be interested in art as a subject or as a hobby.
On the other hand, options like the number of art classes taken, time spent in art museums, and the number of art books owned can serve as operational definitions of interest in art as they provide measurable indicators of engagement and involvement with art.