The correct answer is:
(C) desire to promote trade among the states
This is because the desire to promote trade among the states was not a primary concern that led to the calling of the Constitutional Convention of 1787. The major concerns that led to the convention included dissatisfaction over safeguards of individual rights and liberties, fear for the stability of the central government, the need to give the central government the power to levy taxes, and dissatisfaction with the central government's ability to provide for national defense. The promotion of trade among the states was not a significant factor in calling for the convention.