Final answer:
The abbreviation for a pathological condition of the eye muscles is B) XT, representing exotropia.
Step-by-step explanation:
The abbreviation that stands for a pathological condition of the eye muscles is B) XT, which refers to exotropia. Exotropia is a form of strabismus where the eyes are deviated outwardly. It is not to be confused with PRK, which stands for photorefractive keratectomy, a type of laser eye surgery; or VA, visual acuity; or EM, which does not specifically relate to a pathological condition of the eye muscles.