I believe the answer is a) the scientific method involves developing and testing questions
if they are all part of the same species it would be a population
Explanation:
Nondisjunction: Failure of paired chromosomes to separate (to disjoin) during cell division, so that both chromosomes go to one daughter cell and none go to the other. Nondisjunction causes errors in chromosome number, such as trisomy 21 (Down syndrome) and monosomy X (Turner syndrome). It is also a common cause of early spontaneous abortions
Explanation:
Results in a decline in CD4+T cell numbers below the critical level, and loss of cell-mediated immunity. Therefore the body becomes progressively more susceptible to opportunistic infections and cancer.