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
In which of the condition "PIGGY BACK" wedging is indicated? 
Select and explain. 
A. Proximal caries with gingival recession, B. Tooth with fluted surface, C. Class II with wide proximal box, D. Narrow class II cavity
A: Proximal caries with gingival recession
Answer: A: Proximal caries with gingival recession 
Explanation: None