In the Experiment by Triplett (1898), Considered the First in Social

In the experiment by Triplett (1898) , considered the first in social psychology, what was the hypothesis?

A) leaders must be consistent with their followers
B) people tend to obey orders from authority figures
C) cyclists ride faster when paced by other cyclists than when cycling alone
D) people in crowds develop a 'group mind'
E) social norms influence how we perceive objects and events