The post object field contains options to customize your field:
- Post type: You can filter the choices by selecting post types.
- Filter from Taxonomy: You can filter the choices even more by selecting specific taxonomies / categories
- Multiple: By ticking the multiple option, the select field will now allow multiple selections and the API will return an array instead of a single value.
- Allow Null?: If selected, the select list will begin with a null value titled “- Select -”