Fact 1: Lymphocytes are the key cells involved in the immune response.

Fact 2: An allergy attack is an immunal response.

Given the two facts above, answer the question "What are the key cells in an allergy attack?" with the following options: 
- layers of fat
 - Lymphocytes.
 - fur and fat
 - bone cells
 - muscle cells
 - the skin
 - Red blood cells
 - animals


 

  Lymphocytes.       