Which sentence uses the time-related term correctly? A: Peter enjoys reading about American history, especially the last 40 years, or four decades.

B: Peter enjoys reading about American history, especially the last 40 years, or four millennia.

C: Peter enjoys reading about American history, especially the last 40 years, or four centuries.

D: Peter enjoys reading about American history, especially the last 40 years, or four eras.