Which of the following conditions may involve the misdirection of eyelashes?

Entropion is a condition where the eyelid, typically the lower eyelid, turns inward against the eyeball. This inward turning can cause the eyelashes to rub against the cornea and conjunctiva, leading to irritation, discomfort, and potentially more serious issues such as corneal abrasions or ulcers. The misdirection of eyelashes in entropion is a significant feature of this condition and contributes to the associated symptoms.

In contrast, conditions such as blepharospasm involve involuntary eyelid spasms but do not specifically cause eyelashes to misdirect. Ptosis refers to the drooping of the upper eyelid, which may not involve any abnormal positioning of the eyelashes themselves. A hordeolum, or stye, is an infection in the eyelid's oil glands that can lead to swelling and discomfort, but it does not result in misdirected eyelashes. Therefore, among the options provided, entropion is the condition most directly associated with the misdirection of eyelashes.