Fact 1: Plasma cells are activated B cells that secrete antibodies.

Fact 2: Antibodies are produced to fight antigens.

Given the two facts above, answer the question "what do plasma cells secrete?" with the following options: 
- Chemical energy
 - h2o
 - oxygen
 - antigen fighters
 - harmful substances
 - bioaerosols
 - mucus
 - Organic compounds


 

    antigen fighters     