In the past most pilots have been men, but today the number of women ______ this field is climbing.

A．preoccupied
B．onerous
C．trifling
D．omnipresent

A．support Alcoholics Anonymous as a means of coping with alcoholism
B．present a learning paradigm that will help alcoholics to understand what causes their dependence upon alcohol
C．explain the application of a psychological approach to alcoholism
D．help researchers to formulate workable hypotheses about the treatment of 'alcoholism