Final answer:
A colonoscopy is likely to reveal colon cancer in this case due to the symptoms and findings.
Step-by-step explanation:
The 64-year-old male is experiencing crampy abdominal pain while passing stool along with blood in his stool. Decreased bowel sounds and weak pulses in the right femoral and dorsalis pedis suggest a vascular issue. Given the symptoms and findings, a colonoscopy is likely to reveal b) Colon cancer. Colon cancer can cause abdominal pain, blood in the stool, and can also affect blood flow to the lower extremities.