## Core Concept
The question pertains to the complications associated with renal transplantation, a major surgical procedure for patients with end-stage renal disease. Complications can be immediate or delayed and may involve the graft, the recipient's systemic health, or the effects of immunosuppression. Understanding these complications is crucial for managing patients post-transplant.

## Why the Correct Answer is Right
Hyperacute rejection is a very early and severe form of rejection that occurs within minutes to hours after transplantation. It is primarily due to pre-existing antibodies against the graft, often because of ABO blood group incompatibility or sensitization to HLA antigens from previous transplants, blood transfusions, or pregnancies. This immediate reaction leads to thrombosis and graft necrosis. Given its immediate nature, it is not considered a long-term complication like chronic rejection, drug toxicity, or post-transplant lymphoproliferative disorders.

## Why Each Wrong Option is Incorrect
- **Option A:** Chronic rejection is indeed a complication of renal transplant. It occurs over months to years and involves gradual loss of graft function due to fibrosis and vascular changes within the graft.
- **Option B:** Drug toxicity, particularly from immunosuppressive drugs, is a significant complication. These drugs can cause nephrotoxicity (kidney damage), among other side effects, which can affect the graft and the recipient's native kidneys.
- **Option C:** Post-transplant lymphoproliferative disorders (PTLD) are complications related to immunosuppression. They range from benign lymphoid hyperplasia to malignant lymphoma.

## Clinical Pearl / High-Yield Fact
A key point to remember is that hyperacute rejection is the only type of rejection that occurs immediately after transplantation and is largely due to pre-formed antibodies. This makes **Option D** stand out as different from the other complications listed, which can occur over a longer period post-transplant.

## Correct Answer Line
**Correct Answer: D. Hyperacute rejection**