Final answer:
Giving enemas until clear means administering enemas until the return fluid is free of fecal material, indicating a clean lower intestinal tract, which is essential before certain medical exams or procedures.
Step-by-step explanation:
"Giving enemas until clear" refers to administering enemas to a patient repeatedly until the fluid returning from the bowel is free of fecal matter, implying that the lower intestinal tract has been sufficiently cleansed. This is essential before certain medical procedures, such as a colonoscopy. In contrast to the other options provided, option C correctly defines this phrase: Enemas are provided until the return solution is clear of any fecal material. During enema administration, stool or feces, which the sigmoid colon has shaped and compacted, is expunged from the rectum. Enemas are a means to relieve constipation or clear the bowel, and not related to sensations such as feeling clear-headed or resolving pain. Hence, the objective is to ensure that the stools are removed until the outflowing water is clear, indicating that the colon has been effectively emptied.