Final answer:
If Anisocoria remains unchanged in different lighting conditions and is not accompanied by ptosis, it is likely a normal variation. Horner's syndrome and Myasthenia Gravis present with more symptoms and variations in light conditions.
Step-by-step explanation:
If you have Anisocoria that is equal in dim and bright light without ptosis, the appropriate response would be to consider normal variation. Anisocoria is a condition characterized by unequal pupil sizes, and it can be a normal variation in up to 20% of the population. It is important to rule out conditions like Horner's syndrome which typically presents with additional signs like ptosis (drooping of the eyelid), pupil constriction, and decreased sweating on the affected side of the face. A tumor in the thoracic cavity can impact autonomic functions related to Horner's syndrome by affecting the sympathetic nervous pathway that passes from the hypothalamus down the spinal cord and out to the face and eye. Myasthenia Gravis could also cause ptosis, but wouldn't typically cause Anisocoria without changes in light conditions. Therefore option D) Consider normal variation is the most likely answer.