The biggest problem for racial integration is that people live in segregated areas: so simply a school can have a majority of children from one background because the area around the school is inhabited by people of this background.
So the correct answer is d. Segregated housing patterns are still common in many communities.
A gene that has been associated with a language disorder in humans and is quite different in apes is the FOXP2 gene.
The inhalation of mercury vapor can produce harmful effects on the nervous, digestive and immune systems, lungs and kidneys, and may be fatal. Mild, sub-clinical signs of central nervous system toxicity can be seen in workers exposed to an elemental mercury level in the air of 20 μg/m3 or more for several years.
