Pretend you are a teacher preparing a quiz for the text I will provide. 
            Each quiz question should follow the format below. 
            Ensure that you carefully recheck the questions and answers for accuracy. 
            The output should be a ready-to-use list of dictionaries for the Python eval function:

            [

                    "question": "WRITE THE QUESTION HERE",
                    "options": ["A) OPTION_1", "B) OPTION_2", "C) OPTION_3", "D) OPTION_4"],
                    "answer": INDEX_OF_CORRECT_ANSWER_IN_OPTIONS_LIST,
                    "explanation": "EXPLAIN WHY THE ANSWER IS CORRECT"

            ]

            Text:
            
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Cracks 
5 
Pronounced 
cracks 
that 
extend from developmental 
grooves 
across 
marginal 
ridges to axial walls or from 
the 
margins 
of 
large 
restorations 
may 
cause 
cuspal fracture. When this 
crack 
extends 
through 
dentin or when the patient 
has pain when chewing; the 
tooth requires a restoration 
that 
provide 
complete 
cuspal coverage. 
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enamel is highly mineralized crystalline 
structure containing from 95% to 98% 
inorganic matter by weight. Hydroxyapatite, 
in the form of a crystalline lattice, is the 
largest minerals constituent and is present 
90% to 92% by volume. Other minerals and 
trace elements are contained in small 
amounts. The remaining constituents of tooth 
enamel are an organic content of about 1% to 
2% and a water content of about 4% by 
weight, and these total approximately 6% by 
volume. 
Chemically 
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Hardness may vary over the external tooth 
surface according to the location of the area; 
also, it decreases inward, with hardness 
lowest at the dentinoenamel junction. 
However, dentin is a highly compressive 
tissue that acts as a cushion for the enamel. 
Enamel require abase of dentin to withstand 
masticatory forces. Enamel rods that fail to 
possess a dentin base of caries or improper 
cavity design are easily fractured away from 
neighboring rods. For maximal strength in 
cavity preparation all enamel rods should be 
supported by dentin. 
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Although enamel is very hard and dense 
structure, it is permeable to certain ions and 
molecules, permitting partial and complete 
penetration. The route of passage appears to 
occur 
through 
structural 
units 
that 
are 
hypomineralized and rich in organic content such 
as rod sheaths, enamel cracks, and other defects. 
It appears that water plays an important role as a 
transporting medium through small incrystalline 
spaces. Enamel permeability decreases with age 
because of the changes in the enamel matrix, 
although basic permeability is maintained. This 
decrease is referred to enamel maturation. 
Permeability 
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Deep invaginations occurs in pit and 
fissure areas of occlusal surfaces of 
premolars and molars that decrease 
enamel thickness in these areas. 
These fissures act as food and 
bacterial traps that may predispose 
the tooth to dental caries. Occlusal 
grooves, which are sound, serve an 
important function as an escapeway 
for the movement of the food to the 
facial and lingual surfaces during 
mastication. 
Thank You  
For Your Attention  
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            Quiz: