Final answer:
The most significant piece of evidence that can be traced back to the point of origin or an individual is a DNA sample.
Step-by-step explanation:
The piece of evidence that can be traced back to the point of origin or to an individual with the highest probability and is the most significant is the DNA sample. DNA is unique to each individual, except for identical twins, and can be retrieved from various sources such as hair, blood, or saliva. By comparing the DNA sample to known sources or individuals, scientists can determine if there is a match and establish a connection or identity.