What term describes a stock of plays, dances, or pieces that a company or performer is prepared to perform?

The term that accurately describes a stock of plays, dances, or pieces that a company or performer is prepared to perform is "repertoire." This word specifically refers to the complete range of skills or works that a performer or group can execute, showcasing their readiness and diversity in performance.

In the context of theater or dance, a "repertoire" includes not just the individual pieces themselves, but also implies a level of proficiency and an established selection that performers are known for. It signals to the audience and critics the breadth of what the company can bring to the stage.

The other terms, while related to collections of works or items, do not carry the same specific connotation within the performing arts. "Collection" and "catalog" suggest an organized assembly but lack the implication of performance readiness, while "assortment" implies variety without necessarily indicating a curated selection with performance in mind. Hence, "repertoire" is the most precise term in this context.