Which of Following Statements About G Proteins Associated with G-Protein-Coupled $\alpha$

Which of following statements about G proteins associated with G-protein-coupled receptors is false?

A) G proteins provide a link between the receptor and effector protein.
B) G proteins can propagate the signal by either the G _$\alpha$ or the G _{$\beta$ $\gamma$} components.
C) G proteins are heterotrimeriC.
D) Associated G proteins become active by exchanging GTP for GDP.
E) Activated G protein diffuses away from the receptor.