When Instructing a Client on the Three Steps of a Proctosigmoidoscopy

When instructing a client on the three steps of a proctosigmoidoscopy, which of the following would not be included?

A) Placement of a nasogastric (NG) tube for gastric deflation
B) Digital examination to dilate the anal sphincters to detect obstruction
C) Sigmoidoscope to examine the distal sigmoid colon and rectum
D) Proctoscope to examine the lower rectum and anal canal