Answer #21

The correct answer is A: Color Doppler > 2 D > PW Doppler > M mode

Of these modalities, color Doppler has the lowest temporal resolution. The ultrasound machine sends out a whole packet of acoustic lines across each scan line to generate the color information as well the as the 2D image. 2D requires multiple scan lines and will take longer than a modality with just one scan line. PW Doppler requires time to listen for a signals before sending out another pulse but is along only one scan line. M mode has the highest temporal resolution as it is displaying all data along one scan line over time