How Does Paternity Testing with DNA Work

How does paternity testing with DNA work?

A) DNA strands unique to individuals are matched with the individual's fingerprints, and by comparing those, a scientist can determine if a particular man fathered a particular child.
B) DNA strands unique to the mother and potential father are combined, and if they result in strands identical to the child in question, that man had to be the father.
C) DNA strands unique to the mother, father, and child are compared, and based on their percent similarity, it can be determined with pretty good accuracy if this man was the father of this child (with this mother, but we usually know the mother) .
D) DNA strands unique to the mother, father, and child are compared, and based on their percent similarity, it can be determined with 99% accuracy if this man was the father of this child (with this mother, but we usually know the mother) .
E) If the man's DNA is exactly 50% the same as the child's, he has to be the father.