The most clear example of an ethical dilemma from the provided responses is the scenario involving Lewis. In this situation, Lewis discovers that his roommate is stealing pharmaceuticals, which creates a conflict between his loyalty to his friend (not wanting to "tattle") and his responsibility as a healthcare professional to report illegal behavior. This conflict embodies the essence of an ethical dilemma, where there are competing values and responsibilities that make the decision challenging.
The other scenarios involve personal choices or preferences rather than ethical conflicts.