Which of the following is not one of the three important decisions about how to use limited resources?
a. what should be produced?
b. how should it be produced?
c. who will use what is produced?
d. why is it being produced?

Option C. "Who will use what is produced" is not one of the three most important decision about how to use limited resources.

Explanation:

A limited resource is defined  as the type of resources that  take a relative longer period of time to reproduce or replenish. Some of the most important limited resources are natural gas, oil and coal. When deciding how to use the available quantities of the limited resource, the main questions to ask are, what should be produced, how should it be produced and why is it being produced, in order to determine whether is practical and beneficial to use that resource. Despite the fact that considering who will use the resource is not entirely wrong, the question would not be included in the main three, and more as a secondary position to consider.

i am pretty sure it is d.

answer; ///he could not explain why the continents drifted;