A new field is being created on a custom object.

The correct answer is D. Deselect auto add to custom report type.

When creating a new custom field, Salesforce provides an Auto Add option that can automatically add the new field to applicable existing custom report types. If the app builder does not want the new field to appear on pre-existing custom report types, they should deselect the Auto add to custom report type option during field creation. Salesforce release documentation confirms that Auto Add automatically adds custom fields to custom report types based on that object.

Why the other options are incorrect:

Removing the field from page layouts only affects record-page visibility, not report type availability.

Changing profile visibility or read-only access affects field security, not whether the field is added to the custom report type layout.

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