Which Statement Regarding Capillary Electrophoresis Sample Injection Is INCORRECT?
A)Hydrodynamic $\mu$

Which statement regarding capillary electrophoresis sample injection is INCORRECT?

A) Hydrodynamic injection uses a pressure differential between the two ends of the capillary to inject a volume of sample onto the capillary.
B) Electrokinetic injection uses an electric field to inject a volume of sample onto the capillary.
C) For electrokinetic injection,each analyte has a different $\mu$ _app,so the composition of the loaded sample is different from the original sample.
D) For quantitative work,an internal standard is essential because the amount of sample injected is not reproducible between runs.
E) Stacking concentrates the sample cations and anions in the sample at the interfaces between the sample plug and run buffer.