**Core Concept**
The question tests knowledge of **ototoxicity**, specifically which drugs primarily affect the **vestibular system** versus the **cochlear system**. Ototoxicity refers to the potential of certain substances to cause damage to the ear, leading to hearing or balance problems.

**Why the Correct Answer is Right**
Since the correct answer isn't specified, let's discuss a common drug that is mainly toxic to the vestibular system. **Gentamicin**, an aminoglycoside antibiotic, is known for its vestibulotoxic effects, causing symptoms like vertigo and imbalance. This is due to its effect on the **hair cells** of the vestibular apparatus.

**Why Each Wrong Option is Incorrect**
**Option A:** Assuming this could be a drug like **streptomycin**, another aminoglycoside, it is indeed vestibulotoxic.
**Option B:** If this were **kanamycin**, it's more cochleotoxic, affecting hearing.
**Option C:** Possibly **tobramycin**, it can cause both vestibular and cochlear toxicity but is more known for the latter.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that **aminoglycosides** can be either cochleotoxic or vestibulotoxic, with some drugs having a predilection for one over the other. Recognizing which drugs are more likely to cause vestibular symptoms is crucial for managing patient care.

**Correct Answer:** Not provided, however, an example could be **D.** **Kanamycin**, as it is more cochleotoxic.