Universities are _____ of accommodation, so some students have to live out.

A. short   B. out 

网友的这个句子应选 short，be short of sth 在此表示“不够”“缺乏”，英语词典对它的解释是：if you are short of something, you do not have enough of it

Universities are short of accommodation, so some students have to live out.

句意：大学的宿舍不够住，所以有些学生只好住在校外。

至于 be out of sth，它有很多意思，其中与 be short of sth 意思相对比较接近的用法是表示“没有”，可理解为：If you are out of something, you no longer have any of it. 例句如：

The printer is out of paper. 打印机没有纸了。

Red boots are out of stock. 红靴子没有现货。

The shops are out of bread. 店铺里没有面包了。