The correct answer is A because the user only needs to query the data, which requires the ability to view the dataset and run queries. This is provided by roles/bigquery.dataViewer and roles/bigquery.jobUser, aligning with the principle of least privilege.

• Option B is incorrect as roles/bigquery.dataEditor grants more privileges than necessary.
• Option C is incorrect because roles/bigquery.user includes permissions beyond what's needed for querying.
• Option D is incorrect as roles/bigquery.dataOwner provides excessive privileges for the task at hand.

Refer to the GCP documentation on BigQuery Access Control for more details.