Final answer:
The Barium enema and Pyelogram examinations require dietary restrictions before testing; thus, the correct answer is C - 1 and 2 only.
Step-by-step explanation:
The examinations that require restrictions of a patient's diet are the Barium enema and the Pyelogram. A Barium enema, which examines the lower gastrointestinal tract, often requires the patient to follow a clear liquid diet for 1-3 days before the test and may also require a laxative or an enema to ensure a clean bowel. A Pyelogram, which includes tests such as Intravenous Pyelogram (IVP) to evaluate the urinary tract, typically requires fasting and may necessitate following certain dietary restrictions leading up to the test. The Metastatic survey, which detects the spread of cancer to other parts of the body, does not usually require dietary restrictions prior to imaging procedures. Therefore, the correct answer is C - 1 and 2 only.