The U.N. came into existence fully in _____.

A．why some people can hear better than others
B．what can be done to help the hearing impaired
C．how this new auditory test is conducted
D．which hearing problems are the most severe

A．It will reduce misdiagnoses of hard-to-test patients.
B．It will lead to a cure for congenital deafness.
C．It will eventually make other means of testing hearing obsolete.
D．It will win Nobel Prize for outstanding achievement in the field of medicine.