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
Preventive Resin Restoration are indicated in 
Select and explain. 
A. Non cavitated pit and fissures, B. Deep caries to prevent progress of lesion, C. Cavitated fissures which require restoration, D. Wide cavity to prevent cusp fracture
C: Cavitated fissures which require restoration
Answer: C: Cavitated fissures which require restoration 
Explanation: Preventive resin restoration (PRR) is a thin, resin coating applied to the deep pits and grooves or cavitated fissures of young permanent teeth. Simonsen in 1978 described this technique. In addition to restoring the caries, the remaining pits and fissueres are protected with sealants. PRR is also called as conservative adhesive resin restoration.
Depending on the extent and depth of the lesion, there are 3 types of PRR:
Type A- Suspicious pits and fissures where caries is limited to enamel.
Type B- Incipient lesion extending into dentin that is small and confined
Type C- Deep caries thereby requiring greater exploratory preparation in dentin.