The Alamo became a battleground during the Texas Revolution because it -

a more perfect union: the creation of the u.s. constitution. the vote was unanimous. saddled with this weak government, the states were on the brink of not to lend a hand to any proceeding that seemed to pose a threat to that protection. delegates from virginia and other large states demanded that voting in

2686-2181 bce-- "egyptian civilization developed along the nile river in large part because the river’s annual flooding ensured reliable, rich soil for growing crops."

1069-664 bce-- "ancient egyptians developed wide-reaching trade networks along the nile, in the red sea, and in the near east."

the answer would be:

b. race

independent innovation during the abbasid caliphate