Which sentence BEST illustrates the author's purpose?

A) [T]he identification of the criminal's own fingerprints may be the most important tool in the conviction of a criminal.
B) The unique combination of the loops, arches, and whorls determine the shape of the ridges on a person's fingertips.
C) If a match is found, further matching is done by an expert to declare an exact match.
D) Computers and lasers can develop an entire set of prints from these small traces.