An absentminded researcher follows the steps of Figure 11.3, and when the gradient is viewed under UV

Question:

An absentminded researcher follows the steps of Figure 11.3, and when the gradient is viewed under UV light, the researcher does not see any bands at all. Which of the following mistakes could account for this observation? Explain how.
A. The researcher forgot to add 14N-containing compounds.
B. The researcher forgot to add lysozyme.
C. The researcher forgot to turn on the UV lamp.