<prompt> Stain used to diagnose premalignant lesion of lip is?Crystal violetH EToluidine blueGiemsa  <response>: ANSWER: C Toluidine blueREF: Indian journal of dental research 2007 Volume: 18 Issue: 3 Page: 101-105, Mehrotra et al. Molecular Cancer 2006 5:11 doi: 10.11861476-4598-5-11 Mitotic index is a clinically important parameter in cancer pathology. Selective histochemical stains like toluidine blue, Giemsa and crystal violet have been used in tissues including the developing brain, neural tissue and skin. Toluidine Blue detect efficiently and rapidly mitotic figures in sections of formalin-fixed paraffin-embedded human tissues especially in oral cavity 