Which of the Following Statements About Chromosomal Abnormalities Is FALSE

Which of the following statements about chromosomal abnormalities is FALSE?

A) The most common chromosomal abnormality at birth is Down syndrome.
B) Both CVS and amniocentesis are done to detect chromosomal abnormalities.
C) CVS can be performed at any time before a woman gives birth.
D) Amniocentesis can be performed between weeks 14 and 18.