Answer:
The difference between gross physical evidence and trace physical evidence is that B. Gross physical evidence is easily seen, while trace evidence is very small.
Step-by-step explanation:
Gross physical evidence refers to any tangible object found -and easily seen- at the scene of the crime, and may include weapons, biological material and all sort of prints (because they can be pulled off and turned into a legal representation for the purpose of analysis.)
Trace evidence refers to a very small piece of evidence that was left at the crime scene that the investigators use to identify or make connections with a suspect of the crime. These trace materials may include hair, fibers, feathers, soil, etc.