Kelley et al., (2002) used fMRI to identify specific regions of the brain that are active when people judge trait adjective are in uppercase letters, described George W. Bush, or described themselves. Compared to baseline recordings, fMRI indicated that medial prefrontal cortex (PFC) was more involved in judgments about the self than about Bush or the typeface of the letters. This indicates that the PFC is: A) the only brain region that comes into play when people think about themselves. B) one region that comes into play when people think about themselves. C) the biological component of the self. D) the biological basis of personality.