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
Diascopy is very helpful in the diagnosis of – 
Select and explain. 
A. Cutaneous vasculitis, B. Nevus anaemicus, C. Lupus vulgaris, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: Diascopy is of particular value in detecting granulomatous nodules, which have a translucent brownish colour known as 'apple jelly' nodules, e.g. in lupus vulgaris. In Naevus anaemic, localized vasoconstriction, other pigments are unaltered - diascopy of adjacent skin, therefore, reveals an identical colour to that of the depigmented area.
By contrast, diascopy of skin adjacent to vitiligo, in which there is a loss of melanin, demonstrates that the vitiligo remains paler. Application of medium pressure to a spider naevus can compress radiating arterioles and allow visualization of pulsatile flow in the feeding vessel. Palpable purpuric lesions that do not blanch on pressure (diascopy) suggest vasculitis.