Because B.C stands for Before Christ and A.D means the year of our lord so historians took a turn from the traditional christian time method and made it B.C.E (before common era) and C.E (common Era)
Christopher died May 20, 1506
<span>The
challenge that early farmers did not face as a result of the change from a
nomadic lifestyle to an agricultural lifestyle could be early death caused by
disease. Because in agricultural lifestyle, the nomads are now trying to
establish a boundary between their food to eat and food to sell or exchange. It
could also be a challenge for them to clear and cultivate lands because of the
lack of resources.</span>
I think it might be A. but i am not 100% sure so please don’t be mad if it’s wrong, and good luck!!