In dbt, grants can be configured globally, at the project level, or directly inside a model using the config() function. When a grant is set in dbt_project.yml, it becomes a base definition, and individual models may extend (append to) or override that configuration.

According to dbt documentation, prefixing a grant with a plus sign (+) means “extend the list defined in higher-level configurations.”

Thus, if the project-level config already sets:

select: ['reporter']

…and a model needs to add an additional role (here, bi) without removing the existing one, the correct syntax is:

{{ config(grants = { '+select': ['bi'] }) }}

This tells dbt: “Take the existing grant list (reporter) and append bi to it.”

Option B is incorrect because '+bi' is not a valid grants syntax.

Option C is invalid because grants do not use an inherits parameter.

Option D is invalid because include: is not a grants configuration key.

Therefore, Option A correctly applies dbt’s documented merging behavior for grants.