Alain Resnais's Providence and Francis Ford Coppola's the Conversation Both

Alain Resnais's Providence and Francis Ford Coppola's The Conversation both contain examples of

A) major characters whose voices are heard but who never appear on-screen.
B) scenes so dimly lit that sound becomes the main source of narrative information.
C) uses of sound that creates ambiguities.
D) the use of multichannel recording to create a dynamic sense of moving through space.