**Core Concept**
Topical antifungals are used in keratomycosis to treat fungal infections of the cornea. The treatment goal is to eradicate the fungal infection while preserving the integrity of the cornea.

**Why the Correct Answer is Right**
Amphotericin B (Option C) is a polyene antifungal that has been used topically to treat keratomycosis. Amphotericin B binds to ergosterol in the fungal cell membrane, forming pores that disrupt fungal cell membrane integrity and ultimately leading to fungal cell death. This mechanism is specific to fungal cell membranes, which contain ergosterol instead of cholesterol found in human cell membranes.

**Why Each Wrong Option is Incorrect**
**Option A:** Natamycin is the correct answer, not natamycin.
Natamycin is a polyene antifungal that has been used topically to treat keratomycosis, and it is the correct answer, not natamycin.

**Option B:** No information is available about this option.
There is no information available about this option, and it is not a commonly used antifungal in the treatment of keratomycosis.

**Option D:** No information is available about this option.
There is no information available about this option, and it is not a commonly used antifungal in the treatment of keratomycosis.

**Clinical Pearl / High-Yield Fact**
Amphotericin B can cause corneal toxicity when used topically, especially at high concentrations. It is essential to use the drug at the recommended concentration and to monitor the patient's corneal health closely.

**Correct Answer: C. Amphotericin B**