Which artifact causes a simple cyst to appear to contain debris?

Comprehensive and Detailed Explanation From Exact Extract:

Slice thickness (elevational resolution artifact) occurs when the ultrasound beam partially includes surrounding tissue above or below the scan plane, falsely appearing as internal echoes within an otherwise anechoic cyst.

Principles and Instrumentation:

"Slice thickness artifact occurs when off-axis echoes are included in the imaging slice, falsely creating internal echoes in cystic structures."

Refraction (A) causes displacement.

Enhancement (B) causes posterior brightening.

Range ambiguity (D) produces incorrect depth placement.

Therefore, the correct answer is C: Slice thickness.

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