Final answer:
The blood supply to the pelvic section of the ureters comes from the internal iliac artery.
Step-by-step explanation:
The vascular supply for the ureters in the pelvic section primarily comes from the internal iliac artery. This artery is a branch from the common iliac arteries and is responsible for supplying blood to structures in the pelvis, such as the urinary bladder, walls of the pelvis, and in females, reproductive organs including the uterus and vagina.
The internal iliac artery provides the necessary blood supply to the ureters as they pass through the pelvic region. It branches from the common iliac arteries and supplies blood to the urinary bladder, walls of the pelvis, external genitalia, and the medial portion of the femoral region. In females, it also provides blood to the uterus and vagina.