Fiber-optic trans-illumination (FM) method of caries
diagnosis is based on the principle of:: (A) When Laser beam falls on carious enamel, it gives a bluish hue., (B) A fluorescent dye is taken up by carious dentine which can be viewed easily, (C) There	is	a	different index	of	light	transmission	for decayed or sound enamel., (D) The conductance of normal and decayed tooth tissue is different.
Answer is C. None