External beam radiation is planned for a patient with cancer of the colon. Because the treatment area is in the lower abdomen and pelvic area, which of the following measures should the nurse teach the patient is important to prevent complications from the effects of the radiation?
a) Maintain a high-residue, high-fat diet.
b) Test all stools for the presence of blood.
c) Inspect the mouth and throat daily for the appearance of thrush.
d) Perform perianal care with sitz baths and meticulous cleaning.