Final answer:
The meaning of 'art' in the context of the actress practicing for Broadway encompasses both 'performing arts' and 'skill or craft', as theatre involves the skilled live presentation of a performance. Option 3 is correct.
Step-by-step explanation:
The meaning of art that applies to its use in the sentence 'the actress practiced her art in summer stock before performing on Broadway' is most closely related to the concept of the performing arts.
Given the context where the actress practices and performs, it refers to an application of skill in a realm that includes disciplines like theatre, which is a form of creative expression and live presentation. Hence, the definition of art as skill or craft in the particular context of performing for an audience is also implied.