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
Extraction of mandibular first molar in an 8 year old child is known as: 
Select and explain. 
A. Wilkinson's extraction, B. Compensatory extraction, C. Serial extraction, D. Orthodontic extraction
A: Wilkinson's extraction
Answer: A: Wilkinson's extraction 
Explanation: Wilkinson Extraction 
Wilkinson advocated extraction of all the four first permanent molars between the age of 8 ½ & 9 years. 
The basis of it is the fact that first molars are highly susceptible to caries. 
The other benefits of extracting first molars at an early age are:

To avoid third molar impactions by providing additional space for their eruption.  
To reduce crowding in the arch.