**Response:** - Testimonies, although they can vary wit…

**Response:**
- Testimonies, although they can vary with time, align in their core elements. Multiple survivor accounts from different camps corroborate the methods and conditions.
- The physical evidence, while some has been destroyed or hidden, enough remains to confirm mass extermination, like the presence of Zyklon B residues in gas chambers.
- It's also worth pointing out that early on, much of the evidence was hidden or destroyed by the Nazis themselves, which can explain some of the gaps.