What did the publication of the pentagon papers reveal to the american public?

a.
that president johnson was secretly trying to get the u. s. involved in a conflict with china during the later years of his presidency
b.
that robert kennedy had been assassinated by an extremist plot inside the united states government
c.
that military officers and government officials were deceiving the people of the united states about how the vietnam war was going
d.
the president nixon had secret recordings of the illegal activity he conducted while in office