Which is the best completion to maintain parallel structure in Cinderella's tasks?

Maintaining parallel structure in a series of tasks means ensuring that all elements in the list follow the same grammatical form. In Cinderella's tasks, the completion "to air out the laundry" uses the infinitive form of the verb, which aligns with a common structure for listing activities. This form creates a uniformity in language that enhances clarity and flow.

In contrast, other options like "to be airing out the laundry" introduces a continuous aspect that can disrupt the parallelism in the list. "To have aired out the laundry" shifts the tense to the perfect form, which can imply a different time frame than other tasks, while "air out the laundry" changes it to an imperative mood, which does not match the format of the other options. Using the infinitive form "to air out the laundry" keeps the tasks consistent and ensures that they read smoothly together.