先天性巨结肠在钡剂灌肠以前应注意的有关事宜包括（）

A.重复洗肠

B.肛管不宜放置过高

C.不用泻药

D.调节钡剂用等渗盐水

E.钡剂注入不宜过快

With respect to claiming compliance with the CFA Institute Code of Ethics and Standards of Professional Conduct, which of the following statements is least accurate A firm:（）

A. is encouraged to adopt the Code of Ethics and Standards of Professional Conduct as the company's code and ethics.

B. can claim compliance if its code of ethics has been verified by CFA Institute.

C. can claim compliance after ensuring its code of ethics meets the principles of the Code of Ethics and Standards of Professional Conduct.