一道GRE逻辑题求教

一道GRE逻辑题求教
No.6第三套题的一道逻辑题：
Nursing homes range from three to five stories in height. If a nursing home room is above the first floor, it has a fire escape.
If the above statements are true, which of the following must also be true?
A. First-floor rooms in nursing homes do not have fire escapes.
B. Fire escapes are allowed but not required for first-floor rooms in nursing homes.
C. Some nursing homes have no fire escapes.
D. Not all nursing homes have proper fire escapes.
E. Second-floor roomes in nursing homes have fire escapes.
希望知道的同学给点帮助,分析一下答案.谢谢~