Which scanner has the highest spatial resolution based on Hounsfield units and line pairs?

The highest spatial resolution based on Hounsfield units (HU) and the measurement of line pairs per centimeter (lp/cm) is represented by the choice with a water phantom average of 1.0 HU and 14 lp/cm.

Spatial resolution is a critical parameter in CT imaging, indicating the ability of the scanner to differentiate between two closely spaced objects. The measurement of line pairs per centimeter helps quantify this capability, with a higher number indicating better resolution. In this case, the option presents the highest value of 14 line pairs per centimeter, which signifies that this scanner can resolve finer details compared to the other options.

Additionally, the Hounsfield unit of 1.0 suggests a positive contrast relative to water, which can indicate effective image contrast and tissue differentiation. This is valuable in accurately delineating structures in CT images.

Therefore, due to both the highest number of line pairs and the favorable Hounsfield unit, the selected answer demonstrates the optimal conditions for achieving superior spatial resolution in CT imaging.