During the early years of World War I, which of the following did the Germans use to great advantage?
A. the field telephone
B. the machine gun
C. the submarine
D. the tank

The Germans used Submarines to sink ships whether they were military ships or civilians

In my honest opinion I’m not sure but most likely C

The  pan-african movement  was an "emotional, cultural, psychological and ideological  movement  that began among the  african  dispora in the western hemisphere, for a closer  purpose, so that  african  people could feel secure, attain political, economic as well as psychological power visa vis other races or world regions" .