Which of the following abbreviations relates to an eye condition?

The abbreviation that relates to an eye condition is "optic." This term refers specifically to anything pertaining to vision or the eye. For example, it is commonly used in medical contexts to describe the optic nerve, which is crucial for transmitting visual information from the eye to the brain.

The other options, while related to medical terminology, do not pertain specifically to the eye. "Otic" refers to the ear and is used in contexts related to ear conditions or treatments. "PR" typically stands for "per rectum," which is a route of administration for medications and not directly related to eye conditions. "PRN" stands for "pro re nata," meaning as needed, which is a dosing instruction that applies generally to medications rather than a specific eye condition. Thus, "optic" is the most relevant term in the context of this question.