Promised open gays in military but compromised with DADT.
Do the hard work of bridging racial divisions.
Mesopotamia was located in parts of the areas now known as Iraq, Turkey, Syria, and Iran.
One could make the argument for any one of the aforementioned events. However, I would have to argue that the Louisiana Purchase was the most significant for a few different reasons:
1) Jefferson used the concept of implied powers in order to buy this land from France. Nowhere in the US Constitution does it say that presidents can buy land from foreign countries. However, Jefferson argues that this power can be implied. Due to Jefferson's actions, several presidents after him will follow suit and buy territories from other countries.
2) It doubled the size of the United States.
3) It initiated the US's policy of Manifest Destiny. This concept that America should control all land from the Atlantic to Pacific Ocean was one that was introduced in the early 19th century. The first big land annexation of this time was the Louisiana territory (1803). After this purchase, the US would continue to grow in size thanks to buying land from other countries and war.
B is the answer B as in HEY BETTER
Well, for one, women didn't really want the right to vote (at least not all -- anti-suffragettes were not in favor). One of the major reasons that they did not want the right to vote is that it could bring them into conscription or other war-related activities (which anti-suffragettes were not particularly fond of). Domestic life also seemed more amiable for a lot of women, who were not particularly interested in the state of politics.
As for general anti-arguments, you have the fact that many people did not believe that women would be as knowledgeable on voting/politics as men (also why rich and high-class women were given the right to vote before those who were of a poorer class).