Keep this little phrase in mind: <u>gold, glory, and God.</u> In that order. The reason the Catholic monarchs Isabella and Ferdinand sponsored Columbus was
<u>gold.</u> They wanted to get rich off of gold, which would enable them to increase their wealth and trading power as per the economic system of mercantilism.
<u>glory.</u> They wanted their names to be famous. Two of the islands that Columbus saw were named after the two rulers (Isabela Island and Fernandina).
<u>God.</u> They were highly Catholic (remember the Spanish Inquisition?) and they wanted to spread that, in theory, to the primitive natives.
"<span>Membership in the League could draw the United States into future wars" would be the best option from the list, since the United States was heavily isolationist at this point, especially after fighting in World War I. </span>