What is optional when setting your bid and budget when creating an Audience Ad campaign?

The selected answer option, Selecting ad schedule if wanting to show ads on certain days or times of day, is correct because selecting an ad schedule is optional when setting your bid and budget for an Audience Ad campaign. An ad schedule allows advertisers to choose specific days or times of day for their ads to be shown, which can help optimize ad delivery to align with when their target audience is most active. However, this step is not mandatory, and ads will still be shown outside of a defined schedule if it is not set. On the other hand, providing ad copy, setting a default bid, and providing at least one image are typically required to complete the campaign setup. Therefore, selecting an ad schedule is the optional component in this context, giving advertisers flexibility in how they choose to manage their campaign's timing.