You need to configure IAM access audit logging in BigQuery for external auditors. You want to follow Google-recommended practices. What should you do? 

Answer options:

A. Add the auditors group to the ˜logging.viewer` and ˜bigQuery.dataViewer` predefined IAM roles.
B. Add the auditors group to two new custom IAM roles.
C. Add the auditor user accounts to the ˜logging.viewer` and ˜bigQuery.dataViewer` predefined IAM roles.
D. Add the auditor user accounts to two new custom IAM roles.

C

Reference: https://cloud.google.com/iam/docs/roles-audit-logging