IMO A
Whereas in science students the grey matter that is associated with lower empathizing is more in the medial prefrontal cortex, in humanities students the white matter has a higher density around the right hippocampus.
a) Whereas in science students the grey matter that is associated with lower empathizing is more in the medial prefrontal cortex, in humanities students the white matter--> comparing science students with humanities students
b) Whereas the grey matter associated with lower empathizing is more in the medial prefrontal cortex in science students, humanities students have the white matter that--> comparing grey matter with humanities students
c) Unlike science students, who have in the medial prefrontal cortex more grey matter associated with lower empathizing, humanities students' white matter ---> comparing science students with humanities students' white matter
d) Unlike science students' medial prefrontal cortex that has more grey matter that is associated with lower empathizing, the white matter in humanities students---> comparing science students' medial prefrontal cortex with white matter
e) Unlike grey matter that is associated with lower empathizing,
which is more in the medial prefrontal cortex in science students, the white matter in humanities student---> which should be referring to grey matter.