Which Statement About the Use of Aphids and the Use

Which statement about the use of aphids and the use of dye to study transport in plants is true?

A) Only the former process makes use of living organisms.
B) The former process involves penetration of the stem without the need for cutting, whereas the latter requires a cut.
C) Aphids stay permanently attached to the stem, whereas the dye does not.
D) Aphids can be used to study both phloem and xylem, whereas dye can be used only to study xylem.
E) Neither of these methods gives reliable data about transport in plants.