Ammonoids are good as index fossils because of the following characteristics;
<span>1.      
</span>Their abundance and vast distribution across most shallow
marine waters during the periods
<span>2.      
</span>They have easily recognizable
features, such as shells and the highly crenulated and complex suture, that are well preserved in rocks 
<span>3.      
</span>Their rapid
evolution that can assist determine changes and variations in the then environment 
 
        
             
        
        
        
Answer:
i believe that the awnser is A
Explanation:
 
        
                    
             
        
        
        
 Answer:
The correct answer is- B) Cell walls are made primarily of peptidoglycan
Explanation:
There is a difference between the cell wall of bacteria, archaea, and eukarya. The cell wall of bacteria is primarily made up of peptidoglycan which contains two sugar  N-acetylglucosamine and N-acetylmuramic acid while archaea contain two N-acetyltalosaminuronic acid (NAT) in place of N-acetylmuramic acid which is called pseudo-peptidoglycan.
Eukaryotic cell wall is also different from archaeal and bacterial cell wall and animals in eukaryotes do not have a cell wall. Therefore cell wall made up primarily of peptidoglycan will allow you to classify the organism as belonging to Bacteria but not Archaea or Eukarya.