Fact 1: Antigens are molecules that the immune system recognizes as foreign to the body.

Fact 2: An antigen is a molecule of carbohydrate or protein.

Given the two facts above, answer the question "What are molecules that the immune system recognizes as foreign to the body?" with the following options: 
- Foreign country.
 - Carbohydrates, or proteins.
 - microorganisms
 - Something that causes allergies
 - Molecular structure.
 - Operating system.
 - sub-units of species
 - Organic compounds


 

  Carbohydrates, or proteins.       