Fact 1: Passive immunity lasts only as long as the antibodies survive in body fluids.

Fact 2: Antibodies are also called gammaglobulins.

Given the two facts above, answer the question "passive immunity lasts only as long as what survives in body fluids?" with the following options: 
- Energy.
 - gammaglobulins
 - heat or cold
 - bacteria
 - Chemical energy
 - parasites
 - Leptospirosis
 - Veins and arteries.


 

  gammaglobulins       