Why has there been a decline in state-mandated caste systems?

a.As more women were elected to office, the moral issues surrounding castes overrode the political ones.

b.As more countries industrialized, the Caste System became economically obsolete.

c.The United Nations passed a resolution condemning caste systems.

d.Countries that sanction the Caste System have experienced serious boycotts from other, more enlightened countries.

e.All of the above.