Please help me with this

What would lead a historian to consider two events to have a relationship of correlation rather than causation?

In which sentence is the italicized word used correctly? a) the sloth is a benefactor that primarily feeds on vegetation, insects, and small birds and reptiles. b) the flood victims were eternally grateful to their benefactors who provided them with food, shelter, and clothing. c) the spectators in the stadium all cheered when the benefactor announced the game would go into overtime. d) the benefactors visiting the laboratory were impressed by the complex equipment the scientists used.

What kind of relationship did the soviet union have with the united states in 1945