Exam Platform-App-Builder Topic 5 Question 229 Discussion

Read the stem as an implementation requirement. The proper configuration is D. Roll-up summary. In Salesforce terms, this is a roll-up summary design issue. Roll-up summary fields calculate values from child detail records and store the result on the master. The relationship type and field type decide whether the calculation is available declaratively.
The selected configuration is the professional answer because it is native, declarative, and placed at the right scope. If the requirement later expands, another administrator can inspect the same metadata area and understand how the behavior is being produced. That is far better than a solution that depends on hidden assumptions or user training.
The wrong answers confuse adjacent platform concepts. A (Approval Process) is only a partial match because An approval process is for formal sign-off, not for every automation, display, import, or security requirement.
B (Flow) misses the mark because Flow is broad, but it is not correct unless the requirement is specifically about guided or automated logic. C (Custom object) is not enough: it would require extra assumptions that the scenario does not support. This keeps the build declarative, traceable in Setup, and easier to support when the org changes later.
For roll-ups, a master-detail relationship is usually the key declarative requirement. If the relationship is lookup, Flow, Apex, or an AppExchange tool may be needed instead.
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