Grand Theft Auto, a violent video game, is at the center of a civil lawsuit involving the murder of three men in Fayette, Alabama. The victims, police officers, were killed by 18-year-old Devin Moore who had played Grand Theft Auto regularly for months. The attorney bringing the suit against the makers of the video game claims that Grand Theft Auto taught Devin to commit the murders. Following the game's script, the young man had shot three officers in the head, grabbed the keys to a police cruiser, and fled. Indeed, after his arrest, Devin claimed that, "Life is like a video game, everyone has to die sometime."

A young law student demonstrates the controversial video game and relates the details of its script. Like millions of other gamers, he claims that he plays the game for fun.

Child psychologist, David Walsh, has coauthored research that links violent video games to physical aggression. He offers a possible explanation for the association. Pioneering brain research at the National Institutes of Health indicates that the adolescent brain is not fully developed. Thus, repeated exposure to violent games has greater impact because the prefrontal cortex that enables impulse control is still under construction during the teen years.

Diminished impulse control becomes a particularly important factor in young men who have additional risk factors for criminal behavior. Walsh acknowledges that not every person who plays violent video games will re-enact the game's script. Obviously, multiple influences shape human behavior, including physical aggression.

David Walsh indicates that the brain wiring of the prefrontal cortex is not complete until the:

A. late teens.
B. late twenties.
C. early thirties.
D. early twenties.