What Is a Distinct Advantage of External EFM

What is a distinct advantage of external EFM?

A) The ultrasound transducer can accurately measure short-term variability and beat-to-beat changes in the FHR.
B) The tocotransducer can measure and record the frequency, regularity, intensity, and approximate duration of uterine contractions.
C) The tocotransducer is especially valuable for measuring uterine activity during the first stage of labor.
D) Once correctly applied by the nurse, the transducer need not be repositioned even when the woman changes positions.