Scenario Amanda's Parents Realized That Her Body Was Not Developing Properly

Multiple Choice

Scenario
Amanda's parents realized that her body was not developing properly about the time she was 12 years old. She was shorter than most of her friends and was not going through changes normally associated with female puberty. They took her to a doctor who initially diagnosed Amanda with Turner Syndrome because of her physical features. The doctor ordered a karyotype that confirmed his diagnosis. Amanda was born with only one X chromosome. Although there is no specific cure, the doctor was able to treat her and correct some of the problems associated with the condition. For example, she received growth hormone to improve her growth and estrogen to help her develop the physical changes of puberty.
-Amanda's abnormal number of sex chromosomes resulted from ________.

A) independent assortment of chromosomes
B) crossing over
C) nondisjunction
D) random fertilization