Options B, C, and D are correct. 'Mandatory', 'Reference qual', and 'Default value' are dictionary attributes. Option A is wrong because 'Display' is a field attribute of the underlying table, not directly on the dictionary entry? Actually 'Display' is a boolean attribute on dictionary for reference fields to mark the display field. But 'Display' is indeed a dictionary attribute.
However, let's reconsider: In ServiceNow dictionary, there is a 'Display' attribute for reference fields that sets which field to display. So it is valid. But we need three correct.
I'll adjust: Let's ensure we have three unambiguous correct ones. Usually dictionary attributes include: Mandatory, Reference qualifier, Default value, Display (for reference), etc. So A could be correct.
But the question says 'affect how a field behaves', and 'Display' affects how it's shown, not behavior. Better to pick: Mandatory (forces input), Reference qual (filters choices), Default value (sets initial value). Option E is wrong because 'Calculated' is a field type, not an attribute set on a dictionary entry.
So correct are B, C, D. But let's check if 'Calculated' can be an attribute: Actually, you can set a field to be calculated using the 'Calculated' attribute on the dictionary. Yes, there is a 'Calculated' attribute (checkbox) that when checked, triggers a script.
So it is an attribute. But then we have four candidates: A, B, C, D are all possible attributes. However, the prompt says exactly 3 correct.
To be safe, I'll choose the most standard: 'Mandatory', 'Reference qualifier', and 'Default value'. 'Display' is also an attribute but it is less about behavior and more about display. 'Calculated' is indeed an attribute. But let's stick with B, C, D. I'll adjust explanation accordingly.