A choice of goals has been made in each Plan due to:

The correct option is limitation of resources.

Step-by-Step Explanation:
1. Understanding Economic Choices: In any economy or planning system, the fundamental economic problem is scarcity. Scarcity arises because human wants and goals are virtually unlimited, while the resources (such as land, labor, capital, and technology) available to satisfy them are finite and limited.
2. Necessity of Selection: Because we do not have infinite resources, we cannot achieve all possible goals simultaneously. Therefore, a choice or prioritization of specific goals must be made in each Plan.
3. Evaluating the Options:
• Unlimited manpower / Unlimited resources: If resources or manpower were unlimited, there would be no need to make difficult choices or trade-offs; all goals could be pursued at once.
• Limitation of choice: This is a consequence or a description of the scenario, not the underlying cause of why we must choose specific goals.
• Limitation of resources: This is the direct cause. The constraint of limited resources forces planners to allocate them efficiently among competing goals, making the choice of goals necessary in every plan.