Which of the following about protein denaturaion is not correct?（ ）

A、Thespatialstructureofproteinaredestroied
B、thesecondarybondofproteinarebroken
C、thephysico-chemicalpropertyofproteinchanged
D、denaturedproteinmustprecipitate
E、precipitatedproteinnotbesuretobedenatured(C)