In the Clinical Laboratory, the Primary Problem with the Use

In the clinical laboratory, the primary problem with the use of fluorescent techniques is that:

A) this technique is not a very sensitive technique as compared to other spectrophotometric techniques.
B) the flame may not be hot enough to totally dissociate some of the complexes.
C) many compounds do not fluoresce in their natural state.
D) all of the stray light produced in the instrument cannot be filtered out.