What Is the Current Recommendation for Pregnant Women Regarding Cell

What is the current recommendation for pregnant women regarding cell phone use during pregnancy?

A) Keep your cell phone at a distance when it's not being used and never use it while driving.
B) There are no risks associated with cell phone use during pregnancy. Use your phone anytime you want!
C) Do not use a cell phone at all during pregnancy. Cell phone use during pregnancy is hazardous to the health of the pregnant women and her unborn child.
D) Cell phone use during pregnancy is only dangerous if used while driving - don't talk and drive!