White persistent patch in mouth indicates

Ans. b (Streptococcal infection). (Ref. Diseases of ENT by Bhargava 6th ed. 211)Membrane/White patch on the tongue or oral mucosa is seen in:# Leucoplakia (Premalignant)# Lichen planus (Premalignant)# Behcet's syndrome# Streptococcal infection# Diphtheria (Dirty grey patch)# Vincent's angina# Syphilis# Moniliasis (Oral thrush or Candidiasis)# Aphthous ulcers with slough at the base# Viral pharyngitis# Oral submucous fibrosis and erythroplakia are other premalignant oral lesions.