You are presented with the question "what type of antigens does the immune system recognize as foreign to the body?" and the following answer choices: 
- animals
 - epidermal
 - Allergies
 - negative
 - dangerous
 - graptolites
 - group of atoms
 - homogenous

Now knowing that antigens are molecules that the immune system recognizes as foreign to the body and molecules are a group of atoms, choose the best answer.


 

       group of atoms  