End stage renal disease is the stage when both the kidneys have stopped functioning, the survival of the patient depends on dialysis which is a periodic process of cleaning the patient's blood of wastes or a non functional kidney is replaced through transplantation from a donor.

Immuno-suppressant drugs are prescribed if a patient is suffering from an autoimmune disorder or has undergone an organ transplant like a liver, heart or kidney. This is done to prevent the organ from being damaged by the immune system of the recipient. However, as the immune system is being suppressed the patient/recipient may be prone to infections, sepsis or other pathological conditions.

During a kidney transplant usually the failed kidney is not removed instead the transplanted kidney is placed in the iliac fossa (cavity) Conventionally, the kidney receives blood from the renal artery and the renal vein drains blood into the inferior vena cava. However, since the kidney is placed in the iliac fossa that receives blood from the external iliac artery the transplanted kidney is connected to the external iliac artery and accordingly to the external iliac vein. This is also done to make the further surgeries, if required to be less complicated. So, the correct answer is 'External iliac'

Answer is option B i.e."Internal iliac vein"
The internal iliac vein drains blood from the visceral organs in the pelvic region. The internal iliac vein may double all these veins and tributaries join together to form the inferior vena cava.

Isograft is a tissue or organ transplanted from a donor to a recipient who are identical or monozygotic twins. In an isograft transplantation the chances of rejection are near to nil with identical MHCs as they are genetically identical.

Monkey and humans have evolved into two distinct lineages and are distinct species and therefore have a dissimilar genetic composition. Any transplant between these two organisms is known as a xenograft. Which may be rejected vigorously due to greater than required MHC incompatibility.

Allograft is a tissue or organ transplanted from a donor to recipient of the same species but is genetically different and therefore may face rejection during kidney transplant due to distinct HLA proteins