Which of the following best describes the main way that upton sinclair gathered research for the jungle?
a: he hired investigators to spy on activities in a meat-packing plant.
b: he spent two years doing research in libraries all over america.
c: he went undercover as a worker in a meat-packing plant.
d: he interviewed experts in the meat-packing industry.

Upton Sinclair was a famous novelist and social crusader from California, [ who pioneered the kind of journalism known as "muckraking." His best-known novel was "The Jungle" which was an expose of the appalling and unsanitary conditions in the meat-packing industry. "The Jungle" was influential in obtaining passage of the Pure Food and Drug Act. ]

Protecting and assisting  u.s. citizens  living or traveling abroad; assisting u.s.  businesses  in the international marketplace; coordinating and providing support for international activities of other u.s. agencies (local, state, or federal government), official visits overseas and at home, and other diplomatic efforts.keeping the public informed about u.s. foreign policy and relations with other countries and providing feedback from the public to administration officials.providing  automobile registration  for non-diplomatic staff vehicles and the vehicles of diplomats of foreign countries having  diplomatic immunity  in the united states