If antibodies are large, Y-shaped proteins designed to bind with foreign proteins, then antibodies are large, Y-shaped proteins designed to bind with what?

Answer choices:
- heat or cold
 - Allergies
 - major threat to health
 - Veins and arteries.
 - foreign proteins
 - epidermis and dermis
 - harmful substances
 - wavelengths and photons

 

     foreign proteins     