Final answer:
William Clark was a good choice to co-lead the expedition because of his skills as an explorer and cartographer, his previous military service with Meriwether Lewis, and his abilities as a diplomat and negotiator, making option D (All of the above) the correct answer.
Step-by-step explanation:
William Clark was an ideal choice to co-lead the Corps of Discovery due to his comprehensive range of skills and experiences. Specifically, option D (All of the above) is the correct answer to what made William Clark a good choice to co-lead this expedition. Clark was not only a skilled explorer and cartographer, which was essential for mapping the uncharted territories of the Louisiana Purchase, but he also had a strong military background and had previously served with Meriwether Lewis, who selected him as his co-leader.
Furthermore, his diplomatic abilities were crucial in dealing with Native American tribes along the journey, helping to establish peaceful relations and trade. Clark's multifaceted expertise was pivotal in successfully completing the objectives set by President Jefferson, which included mapping the territory, establishing trade routes, and asserting American claims in the Pacific Northwest. His contributions led to significant advances in geographical knowledge and laid the groundwork for future American expansion.