You Are Estimating the Number of Neurons and Synaptic Connections

You are estimating the number of neurons and synaptic connections in the brains of two patients. Patient A has many more synapses than Patient B. All things being equal, it is likely that

A) Patient A is a child
B) Patient B is a child
C) Patient A is a split-brain individual
D) Patient B is missing part of the corpus callosum
E) Patient A has received a cortical implant