Mark was diagnosed with a moderate intellectual disability and would be described as a loving and responsive child, who is making progress in a specially tailored educational program.Mark's condition is the result of his receiving an extra chromosome from his mother at pair 21.Mark has
A) cretinism.
B) phenylketonuria (PKU).
C) Down syndrome.
D) fragile-X syndrome.

Question

Quizplus · Accepted Answer

Down syndrome is caused by the presence of an extra chromosome, specifically a third copy of chromosome 21. This results in a range of developmental and intellectual disabilities, as well as physical features such as a flattened facial profile and short stature. Mark's description fits the characteristics of Down syndrome.

Mark Was Diagnosed with a Moderate Intellectual Disability and Would