One of the Focus on Neuroscience Sections in the Text

One of the Focus on Neuroscience sections in the text described a study in which German neuroscientists studied people who learned to juggle. One of the findings of the study was that:

A) specific brain regions increased in size by 3 to 4 percent in the nonjugglers but did not change in the jugglers.
B) specific brain regions increased in size by 3 to 4 percent in the jugglers but did not change in the nonjugglers.
C) gray matter in two regions in the brains of novice jugglers decreased by 3 to 4 percent after seven days of daily practice.
D) gray matter in two regions in the brains of seniors who learned to juggle decreased by 3 to 4 percent after seven days of daily practice.