Which Statement About the Tracking of Genetically Modified Ingredients Is

Which statement about the tracking of genetically modified ingredients is correct?

A) Modern technology has made the tracking of all ingredients very easy.
B) Many health problems and even a few deaths have occurred when tracking systems went awry.
C) Labeling of foods containing GM ingredients is only required under very exceptional circumstances like when there are changes in the nutritional composition of the food
D) In the US genetically modified crops are segregated from other crops at all phases of food production.