It can be inferred from the passage that, before the Industrial Revolution, most women worked in______.

A．Mechanization of work has little changed the conditions of women.
B．Mechanization revolutionizes a society's traditional values and customary roles of its members.
C．Mechanization of work creates new jobs that did not exist previously.
D．Women's work has changed considerably in the past 200 years.

A．two competing scientific models concerning the sun's magnetic field
B．an overview of some recent scientific developments in solar physics
C．the reasons why a problem in solar physics has not yet been solved
D．the difficulties involved in linking terrestrial climate with solar activity