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: Dental
Which generation of bonding system combines the primer and bonding agent into a single step? 
Select and explain. 
A. Fourth, B. Fifth, C. Sixth, D. Seventh
B: Fifth
Answer: B: Fifth 
Explanation: FIFTH GENERATION  

To decrease the number of steps PRIME AND BOND WERE COMBINED. 
ETCH +   (PRIME+BOND). 
Called self priming adhesive.  
Bond strength 17-24 MPA. 
Less number of steps less post operative sensitivity. 

Eg: Prime and bond NT, Adper single bond, Opti bond solo.
Reference- Sturdevant 6th ed