Which adjustment will improve visualization of blood flow if color extends outside the boundary of...

Comprehensive and Detailed Explanation From Exact Extract:

When color "bleeds" outside vessel walls, it often results from motion artifacts or noise from slow tissue motion being displayed as flow. Increasing the wall filter eliminates low-frequency Doppler shifts caused by motion, improving color accuracy within vessel boundaries.

According to sonography instrumentation reference:

“Raising the wall filter eliminates low-velocity signals from vessel wall motion, reducing the appearance of color outside the vessel lumen.”

Therefore, the correct answer is C: Increasing wall filter.

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