question: What is the main cause of New Delhi 's relatively low ranking in Mercer 's quality of life survey ?
answer: bad air quality and pollution
turker_answer: The main cause of New Delhi 's relatively low ranking in Mercer 's quality of life survey is bad air quality and pollution .
rule-based: The main cause of New Delhi 's relatively low ranking in Mercer 's quality of life survey is bad air quality and pollution .