Final answer:
The correct answer is option A. conflicts among the States during the Critical Period.
Step-by-step explanation:
The Framers included the Supremacy Clause in the Constitution due to various influences and conditions that existed during the time of its writing. Primarily, the conflicts among the States during the Critical Period may have led the Framers to ensure a clear hierarchy between federal and state laws. This was necessary to prevent the kind of legislative chaos that had emerged under the Articles of Confederation, where federal weakness had led to interstate disputes and difficulties in enforcing national policies.
The Supremacy Clause, found in Article VI, clearly states that the Constitution, and the laws of the United States enacted thereby, are the 'supreme Law of the Land.' This was a critical assertion to overcome the limitations of the federal government's authority at that time. By establishing federal laws as supreme, it resolved potential power struggles by mandating that state courts and officials uphold federal law even if state law conflicted. The significance of this clause was demonstrated in the landmark case of McCulloch v. Maryland, which upheld the supremacy of national legislation over state law, reinforcing the Constitutional framework designed by the Framers.