The sentence " ... government of the people, by the people, for the people, shall not perish from the earth" comes from

A．The study allows doctors to control the part of HIV that’s active in the body quite well.
B．The hidden pool of HIV is named as the reservior through this study.
C．The hidden pool of HIV is lowered modestly in the four patients.
D．The hidden pool of HIV could be reduced more than 80 percent.