Final answer:
The key assumption of biological theories of crime is that genetic factors play a significant role in criminal predisposition. The correct option is b.
Step-by-step explanation:
The key assumption of biological theories of crime is B) Genetic factors play a significant role in criminal predisposition.
Biological theories of crime suggest that certain genetic factors can contribute to an individual's predisposition to engage in criminal behavior. These theories propose that individuals may inherit traits or characteristics that make them more likely to become involved in criminal activities.
For example, some studies have shown a link between specific genes and aggressive or impulsive behaviors, which are often associated with criminal conduct. However, it is important to note that genetic factors alone do not determine criminal behavior, as environmental and social factors also play a significant role. The correct option is b.