It' s obviously not urgent they would have called us straight awayA. or ratherB. or els

问题补充：

It s obviously not urgent, they would have called us straight away．

A. or rather

B. or else

C. rather than

D. other than

答案：

A. or rather

(答案→)B. or else

C. rather than

D. other than

解析：A更正确地说；B否则，要不然；C而不是；D除…之外；句意：很明显那件事情不紧急，要不然他们就会立刻打电话给我们的。