A. However while reading they would not know when to pause and what to emphasize .

B. Since then their use has been regularized and the punctuation rules have been followed by all .

C. In earlier days , people learnt by reading out loud .

D. But not everybody used the same punctuation for the same thing .

E. To address this problem , various signs depicting various punctuation were introduced .

F. Thus , firmer guidelines regarding punctuation were framed so that everyone used them in similar way .

Which of the following sentence should be the FIRST after rearrangement ?