Which of the following is a short-term risk to the eyes from tanning?

Night blindness is a condition that can arise from short-term risks associated with tanning, primarily due to the exposure to intense light and UV radiation. When individuals tan or are exposed to bright lights, particularly UV radiation, it can temporarily affect their ability to adapt to changes in light levels. This temporary adaptation issue may lead to difficulty seeing in low-light conditions, known as night blindness.

It's important to recognize that the other conditions mentioned do not typically result from acute exposure to tanning. Cloudiness of the lens is closely associated with cataracts and is more of a long-term effect. Optic neuritis involves inflammation of the optic nerve and is generally not linked to tanning. Dry eyes can occur from a variety of factors but are not specifically a short-term risk tied to tanning itself. Thus, the physiological effects of tanning on vision are best represented by night blindness as a short-term risk.