The relationship between laboratory examination and health assessment is ( )
选项：

A:Laboratory examination is an important part of health assessment.
B:There is no need to explain to the patient before sample collection.
C:Correct collection and handling of specimens are the basic knowledge and skills that nurses should have.
D:The results of laboratory examination can assist and guide nurses to observe and judge the condition.
E:Laboratory examination results can provide objective basis for nursing diagnosis.