As an undergraduate research assistant, you are assisting with a radioisotope tracer experiment. You expose a mature leaf on one side of the lower shoot of a sugar beet plant to 14CO2 and then track the movement of the 14C atoms by radiography. Where are you least likely to detect 14C?
A) the shoot apical meristem B) a young leaf directly above the treated leaf C) a mature upper leaf on the opposite side of the plant from the treated leaf D) the treated leaf E) the roots