Final answer:
The founders were influenced by Enlightenment ideas and democratic principles in writing the Constitution, drawing from thinkers like John Locke and Montesquieu. a) Enlightenment ideas and democratic principles.
Step-by-step explanation:
The writing of the United States Constitution was heavily influenced by Enlightenment ideas and democratic principles. The founders were inspired by Enlightenment thinkers such as John Locke, who proposed natural rights to life, liberty, and property which Thomas Jefferson adapted to "the pursuit of happiness" in the Declaration of Independence. They also drew upon Montesquieu's idea of a political system with powers divided among more than one branch of government, to prevent any one branch from becoming too powerful, and desired a federal republic where states retained some independent power.
Therefore, the principles that influenced the founders during the writing of the Constitution were Enlightenment ideas and democratic principles (option a). The Constitution represented an innovative blend of the Enlightenment concepts with unique American views on self-government, leading to a new blueprint for government distinct from the monarchical systems of Europe.