Geometry

Question Analysis：
This question checks knowledge of fixed points under reflection across y = x.

Key Concept Explanation:
Points on the line y = x reflect onto themselves. No change occurs.

Step-by-Step Solution：
Since (5, 5) lies on y = x, reflection results in the same point: (5, 5)

Option Analysis：
A. Flipped y
B. Flipped x
C. ✅ Correct — no change
D. Flipped both values

Common Mistakes：
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