They are specialised cells.
        
                    
             
        
        
        
ANSWER: 
Cytokines, Chemokines, Leukocytes, Neutrophils, Macrophages, and Dendritic cells are all involved
EXPLANATION:
On the incidence of Streptococcus, the immune system activates a complex response that relies basically on the instatement and activation of macrophages, neutrophils, and dendritic cells. 
These activities will only occur on the activation of innate immune responses through workout between pattern recognition receptors (PRRs) with streptococcus derived pathogen-associated molecular patterns (PAMPs).
Moreso, cytokines and chemokines (well known are IL-1β and CXCL1 respectively) produced by macrophages and dendritic cells on exposure to Streptococcus, elicits neutrophil.
Neutrophils then produces antimicrobial proteins, reactive oxygen species (ROS) and sometimes neutrophil extracellular traps (NETs), all these for the bacterial infection control.
 
        
             
        
        
        
The answer is <span>Take consistent amounts of saliva samples from a number of people who have not eaten in 8 hours and measure the quantity of amylase in each sample.
First, the researcher needs to know the quantity of amylase in the <u>same</u> amount of saliva. Thus the amount must be consistent and not varying. 
Next, people must not eat in 8 hours, so they are all in the same condition at the moment of collecting saliva. If some eat immediately before the sample collecting while some eat 8 hours before, the content of their saliva will be different. 
For the correct results, all conditions must be the same.</span>
        
                    
             
        
        
        
Answer:
The last one
Explanation:
It just makes more sense because the other continents/places mentioned in the previous answers are too far away to yield such drastic results