This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
Lactobacilli are numerous in carious lesions because they
a They are the main causative agent
b can produce insoluble extracellular polysaccharides
c can attach to smooth enamel surfaces
d are more violently cariogenic for animals than Streptococcus mutans
e are secondary invaders 
Select and explain. 
A. abcd are false e is true, B. abc are false d e are true, C. ab are false c d e are true, D. a is false bcde are true
A: abcd are false e is true
Answer: A: abcd are false e is true 
Explanation: None