Louisa and Her Husband Have Conceived This Month

Louisa and her husband have conceived this month. Which of the following statements is correct?

A) Louisa's infant-to-be will be considered an embryo until approximately the 8^th week
B) Louisa's infant-to-be will be considered a fetus until approximately the 8^th week
C) Louisa's infant-to-be will be considered a fetus and an embryo until the 16^th week
D) None of the above alternatives is correct