Compensation for the variation in echo height related to variations in discontinuity depth in the test material is known as:

• A. Transfer
• B. Distance amplitude correction
• C. Attenuation
• D. Interpretation

Answer: (B)

Distance amplitude correction is the method used to compensate for the tendency of echo heights to decrease as depth increases. By applying a depth‑dependent correction, echoes from deeper discontinuities are amplified in a controlled way so that a flaw of a given size produces a similar indication regardless of its depth. This normalization makes flaw sizing and detection more reliable across the test material. Attenuation describes the actual energy loss with distance, which is what DAC compensates for; the other terms refer to different aspects of ultrasonic testing and are not the depth‑compensation method.