The term "fixed entity" in the first paragraph can best be interpreted as ______.

A．who is unintelligent
B．who is incapable of learning well
C．who comes from a deprived home environment
D．whose parents are poor and segregated

A．condemning the U.S. for its failure to provide better medical care to the poor
B．evaluating the relative significance of factors contributing to the poor health status in the U. S.
C．comparing the general health of the U.S. population with world averages
D．advocating specific measures designed to improve the health of the U.S. population