【单选题】听力原文:The poor living conditions in such a large city have resulted from the unplanned real estate development, which is rarely seen in small cities. What does the speaker mean?
A.
Bad living conditions are due to the poor city.
B.
Bad planning is responsible for poor living conditions.
C.
Living conditions are bad because the city is too big.
D.
Small cities have better living conditions than large ones.