**Core Concept**
Steven Johnson's syndrome (SJS) is a rare, serious disorder of the skin and mucous membranes, often triggered by an adverse reaction to medications, particularly in individuals with a compromised immune system such as HIV-infected patients. This condition is characterized by the formation of blisters on the skin and mucous membranes, which can lead to significant morbidity and mortality if left untreated.

**Why the Correct Answer is Right**
The correct answer is a drug that is known to cause SJS, particularly in individuals with a history of HIV infection. This is due to the drug's ability to trigger a severe immune-mediated response, leading to the characteristic skin and mucous membrane lesions. The drug in question is **Sulfonamides**, which are a class of antimicrobials that can cause SJS, especially in individuals with a history of HIV infection.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because while certain other medications can also cause SJS, they are not as strongly associated with the condition in HIV-infected individuals.
* **Option B:** This option is incorrect because this medication is not commonly linked to SJS in HIV-infected patients.
* **Option C:** This option is incorrect because while this medication can cause skin reactions, it is not as strongly associated with SJS in HIV-infected individuals.

**Clinical Pearl / High-Yield Fact**
In HIV-infected patients, certain medications such as sulfonamides, NSAIDs, and anticonvulsants can increase the risk of SJS. It is essential for healthcare providers to carefully evaluate the medication history of HIV-infected patients before initiating new treatments to minimize the risk of this serious condition.

**Correct Answer:** A. Sulfonamides