Which of the following is specifically true regarding settlement rules within a project definition?

The statement that settlement rules are maintained in the project definition is accurate. In project systems, settlement rules define how costs incurred on a project will be settled to other cost objects, such as internal orders, cost centers, or profit centers. These rules are an integral part of the project definition, as they provide the parameters for how financial transactions related to the project will be processed and subsequently reallocated.

Additionally, settlement rules allow for customization on how costs are managed and can include specifications like how often the settlement occurs and the criteria for cost distribution among different financial objects. By being part of the project definition, they ensure that each project has a defined method through which its financial outcomes will be processed, which is crucial for accurate financial reporting and budget management.

In the context of the other options, while settlement rules can potentially be changed, they might not always be adjusted after the project has been defined. They do not have to be the same for all WBS elements, as different elements within a project may have distinct settlement rules based on their particular needs or purposes. Finally, although settlement rules play a role in cost allocation, they do not dictate budget limits, which are typically established during the planning phase of a project and tracked separately from how costs are settled.