Question: what type of microsoft server serves as an email server
[{'answer': 'Microsoft Exchange Server', 'provenance': [{'wikipedia_id': '508384', 'title': 'Microsoft Exchange Server', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 25, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '508384', 'title': 'Microsoft Exchange Server', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 145, 'bleu_score': 0.9067110266941041, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9173236007668673746}, 'section': 'Section::::Abstract.'}]}]