"We don't fully understand the importance of sleep. What we do know now is that sleep is an anabolic, or building process. And we think it restores the body's energy supplies that have been depleted through the days activities" -Dr. Neil B. Kavey
"Sleep is also the time when the body does most of its repair work; muscle tissue is rebuilt and restored. We know, for example, that growth hormone is secreted during sleep. This hormone is important for growth in children, but is also important throughout adulthood in rebuilding tissues." <span>Dr. Neil B. Kavey, director of the Sleep Disorders Center at Columbia-Presbyterian Medical Center in New York City </span>Here is the link to article: <span>http://www.nbcnews.com/id/3076707/ns/technology_and_science-science/t/why-do-we-need-so-much-sleep/#...</span>
C is definitely correct, but i’m not sure if any of the others apply because i can only find an excerpt of “what is apartheid?”. I hope that helps at least a little
