**Core Concept**
Cyclosporine-A is an immunosuppressive drug that works by inhibiting **calcineurin**, a crucial enzyme in the activation of T-lymphocytes. This inhibition suppresses the immune response, making it useful in preventing organ rejection in transplant patients. Cyclosporine-A also has various side effects due to its mechanism of action.

**Why the Correct Answer is Right**
The correct answer choice is not provided, but we can discuss the general properties of cyclosporine-A. Cyclosporine-A is known for its nephrotoxicity, neurotoxicity, and potential to cause **hypertension** and **hyperkalemia**. It works by forming a complex with **cyclophilin**, which then inhibits calcineurin, preventing the transcription of **IL-2** and subsequent T-cell activation.

**Why Each Wrong Option is Incorrect**
**Option A:** Without the specific details of option A, we cannot directly address why it is incorrect.
**Option B:** Similarly, without specifics, we cannot discuss the inaccuracies of option B.
**Option C:** Again, lacking details, we cannot explain why option C is wrong.
**Option D:** The same issue applies to option D, as the content of these options is not provided.

**Clinical Pearl / High-Yield Fact**
A key point to remember about cyclosporine-A is its narrow **therapeutic index**, requiring careful monitoring of blood levels to avoid toxicity while maintaining efficacy. This is crucial in clinical practice to balance the benefits of immunosuppression against the risks of adverse effects.

**Correct Answer:**