The correct answer is the frontal lobe.
The frontal lobe is an area of the brain that is located just behind the forehead. It is involved in "higher order" complex cognitive processes such as decision making, logic and reasoning. The frontal lobe also houses a key area of the brain known as the prefrontal cortex (PFC). The PFC is responsible for complex cognitive functions, planning, critical thinking, reasoning and personality expression. The PFC develops significantly during adolescence and is related to improvements in inhibiting of behaviors.