During a third-trimester ultrasound, what would a doctor expect to observe the first heartbeat in a fetus.
The method of prenatal development occurs in 3 stages.
The first 2nd weeks after conceiving are called as the germinal stage, the 3rd through the 8th week is called as the embryonic stage, and the time from the 9thweek tillbirth is called as the fetal period.
Thus, option "D" is correct, as other parts develop at a later stage.
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