37. During a liver ultrasound scan, the transducer operates at frequency f = 5.0 MHz. The sound speed in liver tissue is v = 1540 m/s. The emitted ultrasound pulse contains 3 cycles per pulse (i.e., the spatial pulse length (SPL) corresponds to 3 wavelengths). Assume the minimum separable distance along the beam direction (axial resolution) is Δzmin = SPL/2. What is the minimum tumor thickness (along the beam direction) that can be resolved as a distinct structure?
(A) 0.15 mm
(B) 0.23 mm
(C) 0.46 mm
(D) 0.92 mm
(E) 1.54 mm

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