NDA English Sentence Completion

Here, question tag is required in Present Tense. So, use of'have'. It is proper in order to make Subject-Verb agreement in the sentence. Use of negative tags is improper and 'are' cannot be used as Perfect Tense is needed.
Suitable tag structure is as follows;-
Subject+ Auxiliary verb + not + Verb+ Object + [, ] + Auxiliary verb + Subject + ?