The Sprint Retrospective is an event for the entire Scrum Team, including the Scrum Master, to inspect and improve their processes. The Scrum Guide explicitly states that the Scrum Master participates as a peer: 'The Scrum Master participates as a peer team member in the Sprint Retrospective from the accountability over the Scrum Team's effectiveness.' This ensures a collaborative review of the Sprint, including the Scrum Master's facilitation role.

A: True---the Scrum Master is a full participant.

B: False---exclusion contradicts Scrum's team focus.

Exact Extract from Scrum Guide: 'The Sprint Retrospective is an opportunity for the Scrum Team to inspect itself and create a plan for improvements to be enacted during the next Sprint... The Scrum Master participates as a peer team member in the Sprint Retrospective from the accountability over the Scrum Team's effectiveness.' (Section: 'Sprint Retrospective')

Thus, A is correct.