Outline a simple calibration plan for thickness measurement in a new material.

• A. Establish velocity with a known thickness reference, calibrate back wall echoes, create a DAC curve, and verify measurements against additional references.
• B. Do not calibrate; assume standard velocity and proceed.
• C. Only calibrate velocity, ignore DAC and back-wall echoes.
• D. Use a ruler to estimate thickness.

Answer: (A)