Explanation
Correct answer: B.
Choice B is the best answer. “Ultimately” means “in the long run” or “at the highest level.” Although Bolívar wrote to a local merchant, his ultimate goal was to send a message to political leaders in Europe. Therefore, “ultimately” fits perfectly in this context.
Why the other choices are wrong
Choice A
Choice A is incorrect. This choice uses a transition that indicates the addition of an agreeing idea. However, the second part of the sentence actually disagrees with the first part. Bolívar addressed the letter to Cullen, but he was really sending a message to someone else. Notice how the contrast word “though” also acts as a transition between these ideas.
Choice C
Choice C is incorrect. This choice uses a cause-and-effect transition. Bolívar’s writing of the letter to Cullen would not cause him to have a goal of persuading European powers to support him.
Choice D
Choice D is incorrect. This choice uses a cause-and-effect transition. Bolívar’s writing of the letter to Cullen would not cause him to have a goal of persuading European powers to support him.