Final answer:
Organizational structures is not a constraint imposed by organizations on project managers.
Step-by-step explanation:
Of the options provided, organizational structures is not a constraint imposed by organizations on project managers. Organizational structures refer to the way the different departments and roles are organized within the organization, and it does not directly constrain the project manager's decisions or actions.
On the other hand, management elements, operational process assets, governance frameworks, and operational process assets are all constraints that project managers need to work within.