Which of the following is a sign of inadequate cleaning of biological materials?

Strong odors are an indicator of inadequate cleaning of biological materials because they often signify the presence of organic matter, such as blood, bodily fluids, or other contaminants that have not been fully removed. These odors can originate from the decomposition of biological substances, signaling that simply visible cleaning may not be sufficient.

In a thorough cleaning process, particularly in trauma and crime scene situations, it is essential to ensure that all biological materials are effectively cleaned and sanitized to prevent any potential health hazards. The absence of odors is a good sign of effective cleaning, while lingering smells suggest that residues may still be present.

Other choices, such as no visible residue or positive verification tests, do not necessarily imply inadequate cleaning. A lack of visible residue could indicate a successful cleaning effort, while positive verification tests, which are designed to confirm the absence of biological contaminants, further support the effectiveness of the cleaning process. No complaints from clients, while potentially reflective of satisfaction, does not inherently indicate that cleaning was thorough or that all biological hazards have been eliminated.