Because the offer believes the US should be less concerned with foreign affairs, the answer is C, the author supports a greater focus on domestic policy.
Most likely C or D because for C, he likes cowboy cards and wants more, or D, he now knows that without the making of cowboy cards, those cards will increase in rarity and grow more expensive, so he will want his brother to sell them for more money. Your choice.
He inclinations the American individuals to maintain a strategic distance from long-term inviting relations or competitions with any country, contending that connections with or enmity toward other countries will as it were cloud the government's judgment in its outside policy.