A Doppler exam is performed with a 4 MHz transducer. The maximum Doppler shift is measured at 2.5 kHz. If the identical exam is performed with an 8 MHz transducer, what maximum Doppler shift will be measured? A. 8 kHz B. 5 kHz C. 1.25 kHz D. 2.5 kHz E. 4 kHz