Immunodeficiency occurs when the immune system is not working properly, and malnutrition , particularly with lack of protein , can cause acquired immunodeficiency. Given these facts, what can cause the immune system to not work properly among the following options:
- cigarettes
 - Malnutrition
 - burning coal
 - Healthy food
 - Exercise
 - Good health
 - Allergies
 - Pesticides


 

  Malnutrition       