Which Statement by the Patient Scheduled for a Lower Gastrointestinal

Which statement by the patient scheduled for a lower gastrointestinal series as diagnostic evaluation for colorectal diagnosis indicates understanding of the teaching about this procedure?

A) "A stool sample is collected by my doctor by digital rectal examination."
B) "After I have expelled most of the contrast, my intestine is filled with air and x-ray images are taken."
C) "Constipation may occur as a result of this procedure, so I will increase my water and fiber intake."
D) "A flexible tube with a light and camera is inserted into my rectum so that tissue can be biopsied."