Young people who have got jobs may realize university lessons can’t be the only preparation for all the situations _______ appear in the working world.

A．where

B．when

C．that

D．what

当事人超越经营范围订立的合同，除违反国家限制经营、特许经营以及法律、行政法规禁止经营规定的以外，该合同有效。( )