An ISO $9001$ quality audit is a management tool companies use to $$

Evaluate, confirm, and verify activities related to quality.

The ISO $9001$ quality audit determines the effectiveness of an organization's quality management system $($QMS$).$

The ISO $9001$ quality audit is the most common ISO standard for audits.

All are True for ISO $9001$ audit

Only $($b$)$ and $($c$)$ are True for ISO $9001$ audit.