According to the Focus on Neuroscience Box, "Boosting the Aging

According to the Focus on Neuroscience box, "Boosting the Aging Brain," why did researchers look for changes in the hippocampus when studying the effects of aerobic exercise on cognitive functioning and brain health in old age?

A) Changes in the hippocampus are easier to measure than changes in other brain structures.
B) The hippocampus is involved in memory.
C) The hippocampus typically shrinks in this age group.
D) The hippocampus is involved in bodily movement.