David shows delayed intellectual development and has flattened facial features. the doctors explain that this genetic disorder is a result of extra genetic material in the 21st chromosome. which disease is david suffering from?

Down syndrome

Explanation:

Down syndrome is characterized by the presence of one extra copy of chromosome 21. This leads to total of 3 copies of chromosome 21 rather than two copies as it present normally. Since David has extra genetic material in chromosome 21, he is suffering from trisomy 21, that is, Down syndrome.

In Down syndrome, the affected children exhibit slow mental growth, broad head, and round face.  

The disease David is suffering from is B.  

Down Syndrome

Explanation: Plato answer

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