Which of the Following Is True About Prenatal Cell-Free DNA

Multiple Choice

Which of the following is true about prenatal cell-free DNA scans?

A) They have been shown to be useful for early detection of genetic problems.
B) They are noninvasive procedures.
C) They are always definitive and more invasive than amniocentesis and umbilical cord sampling.
D) They can help detect nonchromosomal disorders.