**Core Concept**
The question tests the knowledge of ototoxicity, specifically the comparison of ototoxic effects among various antibiotics. Ototoxicity is a well-documented side effect of certain medications, particularly aminoglycosides, which can cause damage to the inner ear structures, leading to hearing loss or tinnitus. The cochlea and vestibular system are the primary targets of ototoxicity.

**Why the Correct Answer is Right**
Aminoglycosides, such as gentamicin and tobramycin, are known to cause significant ototoxicity due to their ability to bind to the hair cells in the cochlea. This binding disrupts the normal functioning of the hair cells, leading to damage and potentially permanent hearing loss. The mechanism of ototoxicity involves the inhibition of mitochondrial protein synthesis, which ultimately leads to cell death. Other antibiotics, such as vancomycin and fluoroquinolones, can also cause ototoxicity, but aminoglycosides are generally considered to have the highest risk.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is not specified, but it is likely that the other options are ampicillin, cephalexin, or another beta-lactam antibiotic. These antibiotics are not typically associated with significant ototoxicity and are generally considered safe in terms of hearing loss.

**Option B:** This option is likely ciprofloxacin, a fluoroquinolone antibiotic. While fluoroquinolones can cause ototoxicity, they are generally considered to be less ototoxic than aminoglycosides.

**Option C:** This option is likely vancomycin, a glycopeptide antibiotic. Vancomycin can cause ototoxicity, particularly with high doses or prolonged use, but it is generally considered to be less ototoxic than aminoglycosides.

**Clinical Pearl / High-Yield Fact**
Aminoglycosides are generally avoided in patients with pre-existing hearing loss or tinnitus, and their use should be carefully monitored in patients with renal impairment, as they can accumulate to toxic levels.

**Correct Answer:** C. Vancomycin.