Prussian and German statesman

German Chancellor from 1871 to 1890
Nicknamed “The Iron Chancellor”
Leader in German unification movement
All of these are describing what 19th century nationalist leader?
Responses
A Joseph GoebbelsJoseph Goebbels
B Otto von BismarckOtto von Bismarck
C Arthur ZimmermannArthur Zimmermann
D Paul von Hindenburg