Radiology In computed tomography (CT), the attenuation values are measured in Hounsfield units (HU). An attenuation value of ‘0’ (zero) HU corresponds to: A Water B Air C Very dense bone structures D Fat 💡 Explanation In computed tomography (CT), the attenuation values are measured in Hounsfield units (HU). An attenuation value of '0' (zero) HU corresponds to: ✓ Correct Answer: A. Water