Question: a person's income is an example of what kind of market variable
[{'answer': 'Demographic', 'provenance': [{'wikipedia_id': '240342', 'title': 'Market segmentation', 'start_paragraph_id': 14, 'start_character': 134, 'end_paragraph_id': 14, 'end_character': 145, 'bleu_score': 1.0, 'section': 'Section::::History.\n'}]}]