Select the two (2) correctly punctuated sentences.

A) I also explained antepartum fetal surveillance, i.e., fetal heart rate monitoring and assessment of amniotic fluid volume.
B) I also explained antepartum fetal surveillance, i.e. fetal heart rate monitoring and assessment of amniotic fluid volume.
C) I also explained antepartum fetal surveillance, ie, fetal heart rate monitoring and assessment of amniotic fluid volume.
D) I also explained antepartum fetal surveillance, ie fetal heart rate monitoring and assessment of amniotic fluid volume.

My answers are A and B

I see only one that's correctly punctuated -- A.