question: The petroleum industry has become a larger part of Houston 's economy again for what reason ?
answer: the increase of oil prices in the 2000s
turker_answer: The petroleum industry has become a larger part of Houston 's economy due to the increase of oil prices in the 2000s .
rule-based: The petroleum industry has become a larger part of Houston 's economy again for the increase of oil prices in the 2000s .