Final answer:
The correct identification of Horner's syndrome is Ptosis, miosis, anhidrosis (Option C). Horner's syndrome is associated with disruption to sympathetic nerve pathways, which can be affected by a thoracic cavity tumor.
Step-by-step explanation:
The correct set of symptoms and signs that identifies Horner's syndrome is C. Ptosis, miosis, anhidrosis. Horner's syndrome is a condition that affects the sympathetic nerves of the eye and face, resulting in a droopy eyelid (ptosis), a constricted pupil (miosis), and decreased sweating (anhidrosis) on the affected side of the face. A tumor in the thoracic cavity can affect these autonomic functions because the sympathetic pathway that controls these functions passes through the thorax; thus, a tumor in this area can disrupt the normal nerve signaling, leading to the characteristic symptoms of Horner's syndrome. Ptosis refers to drooping of the upper eyelid, miosis is constriction of the pupil, and anhidrosis indicates a lack of sweating. This combination occurs due to interruption of sympathetic nerve signals, often involving the sympathetic pathway from the hypothalamus to the eye, affecting the eyelid, pupil, and sweat glands on the affected side. The disruption can occur at various points along this pathway, such as damage to sympathetic nerves in the neck or chest.