Answer: C. Amebic keratitis
Step-by-step explanation:
Amebic keratitis is a rare but serious infection of the eye that can cause permanent vision loss or blindness. This infection is caused by a tiny ameba (single-celled living organism) called Acanthamoeba. Some of the symptoms of this infection are known as headache, blurred vision, Sensation of something in the eye, Eye pain or redness, Sensitivity to light, Excessive tearing etc..
Some of the ways to prevent this infection is by maintaining a good eye care or hygiene by avoiding swimming in waters infected with germs, washing of hands with antibacterial soap to prevent rubbing eyes with hands infected with germs. Though this infection is rare but can be treated with regimen or drugs prescribed by an eye doctor.