男性 * * 狭窄的原因不包括以下哪项（）

A.感染

B.结核

C.肿瘤

D.创伤

E.膀胱结石

Between 1975 and 1985, nursing-home occupancy rates averaged 87 percent of capacity, while admission rates remained constant, at an average of 95 admissions per 1,000 beds per year. Between 1985 and 1988, however, occupancy rates rose to an average of 92 percent of capacity, while admission rates declined to 81 per 1,000 beds per year.
If the statements above are true, which of the following conclusions can be most properly drawn

A．The average length of time nursing-home residents stayed in nursing homes increased between 1985 and 1988.

B．The proportion of older people living in nursing homes was greater in 1988 than in 1975.

C．Nursing home admission rates tend to decline whenever occupancy rates rise.

D．Nursing homes built prior to 1985 generally had fewer beds than did nursing homes built between 1985 and 1988.

E．(E) The more beds a nursing home has, the higher its occupancy rate is likely to be.