I think the answer is B but I could be wronged
A. cerebellum
B. medulla oblongata
The term that describes the rearranging of genetic material between non homologous chromosomes without a net loss or gain of genetic material is Translocation.
Chromosomes translocation is an abnormality that results from the rearrangement of parts between non homologous chromosomes. A gene fusion may be created when the translocation joins two or else separated genes and is normally detected on karyotype of affected cells.