Question

which is an immune response?
the iris of the eye narrows when the eyes are exposed to bright light.
langerhans cells transport harmful substances to white blood cells.
muscles under the skin contract rapidly to adjust the body’s internal temperature.
t cells signal b cells to adjust the ph of the blood.

Explanation:

To determine the immune response, we analyze each option:

• The iris narrowing in bright light is a reflex for light regulation, not immune.
• Langerhans cells (in skin) are antigen - presenting cells. They capture harmful substances (antigens) and present them to white blood cells (part of the immune system), so this is an immune response.
• Muscles contracting to adjust body temperature is related to thermoregulation, not immunity.
• T cells and B cells are involved in immune responses, but adjusting blood pH is a homeostatic (not immune - specific) process, and T cells don't signal B cells for pH adjustment.

Answer:

Langerhans cells transport harmful substances to white blood cells.