Expecting Mom Giselle Reads About Her Pregnancy on the Website

Multiple Choice

Expecting mom Giselle reads about her pregnancy on the website Mommy-and-Me. She learns that her unborn baby developed noticeable ridges and grooves (termed gyri and sulci) within the cerebral cortex. During which gestational period do these gyri and sulci first become most apparent?

A) 12 to 18 weeks into a pregnancy
B) 18 to 24 weeks into a pregnancy
C) 24 to 30 weeks into a pregnancy
D) 30 to 36 weeks into a pregnancy