Which is appropriate?

Buttons are usually used to fasten clothes, but they are also used to make clothes more fashionable. However, sometimes they have nothing to do with fashion at all. Well, this could be because of Napoleon Bonaparte. It is said that Napoleon wanted to stop his soldiers from wiping their sweat or runny noses with their jacket sleeves. It seems that Napoleon didn’t like his soldier’s bad habit! So, he ordered his tailors to sew buttons on the sleeves so that the soldiers wouldn’t be able to use their jacket sleeves as a handkerchief.__________________________

Which is appropriate for the blank?
(A) Since then, tailors have started putting buttons on the ends of jacket sleeves.
(B) Since then, tailors have been putting buttons on the ends of jacket sleeves.