The correct answer is B. Nondisjunction
Step-by-step explanation:
The nondisjunction is a type of failure that can occur in different stages of cell divisions if chromosomes or sister chromatids do not separate or disjoin as it is expected. This applies to meiosis (type I and II) and also mitosis which leads to cells that have an abnormal number of chromosomes either because they lack a chromosome or they have an extra chromosome. Additionally, nondisjunction often causes genetic disorders such as Down syndrome or Klinefelter syndrome. Thus, the process that occurs when chromosomes do not separate during meiosis is Nondisjunction.