Which type of specialist is responsible for operating on eye diseases?

The correct choice is an ophthalmologist, as this type of specialist is specifically trained to diagnose and treat diseases and conditions of the eye, including performing surgical procedures. Ophthalmologists have completed medical school and additional training in the field of ophthalmology, which allows them to conduct surgery on the eye, in addition to providing comprehensive eye care, such as prescribing glasses and managing eye-related diseases.

Optometrists, while crucial in the eye care spectrum, specialize primarily in vision care and the diagnosis of eye conditions but do not perform surgery. Opticians focus on fitting and dispensing eyewear, assisting patients with frames and lenses but do not have the medical training required to treat eye diseases. Allergists deal with allergic reactions and conditions but do not specialize in eye care, making them unrelated to the question about eye diseases.