IN the scrum guide its mentioned that 'Inspections are most beneficial when diligentlyperfomred by skilled inspectors at the point of work,
Who will be the inspector?
1. Part of Development team?
2. External member than the Scrum team
3. Scrum Master
The Development Team. They are accountable for the quality of their own process, and are in the best position to inspect and adapt it "at the point of work". A Scrum Master may coach Development Team members to do this effectively, but he or she would not perform inspection unless also a member of that team.
Externalized quality assurance is a pathology of non-agile practice, and can lead to unnecessary delay and waste.