<prompt> Hounsfield unit is zero for which of the following___:AirWaterFatDense bone  <response>: Ans. B. Water Water is arbitrarily assigned a value of 0HUHU of different tissues of body: Cortical Bone:1000HU Bright white Solid soft tissue: from 40 to 80HU sometimes upto 300 Acute hemorrhage:45 to65 HU Water: 0HU Grey Fat:-100HU Lungs:-950 to-700HU Air:-1000HU Jet black In CT, bone and hemorrhage are white, air and fat is black. 