An app builder wants to create a formula field on an Account to include data...

The correct answer is C. Unable to reference the child records.

A formula field on Account cannot directly pull data from multiple related Contact records because Contacts are child records of Account. Cross-object formulas work by referencing fields through supported parent relationships, not by traversing from a parent record down to multiple child records. Salesforce documentation describes cross-object formulas as formulas that reference fields on related objects, especially parent records through relationships.

Because an Account can have many Contacts, Salesforce does not expose that child relationship in the formula editor as a single field reference. For summarized child data, the app builder would normally use a roll-up-style solution where supported, or automation such as Flow.

A is unrelated unless the formula has already exceeded character limits.

B is misleading because the core issue is not simply that Account and Contact lack master-detail; it is that formulas cannot directly reference child records.

D is not supported by the scenario.

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