Why does The IIA$$s Code of Ethics in Rule of Conduct $4\mathrm{.}2$ require that due professional care be used in obtaining information to support an engagement opinion?

A$.$Sufficient, reliable, relevant, and useful information lends credibility to the opinion.

B$.$To preclude any conflict of interest.

C$.$To require honesty in performing work.

D$.$If internal auditors were permitted to communicate engagement results without obtaining sufficient information, they would be in a position to accept fees or gifts from engagement clients.