Characteristic lesion in scabies

Ans is 'a' i.e., Burrows Burrow is serpentine (S.shaped), thread like grey brown line which represents the intraepidermal tunnel created by moving female mite in stratum corneum. Burrow is pathognomic sign of scabies. Burrows are very difficult to demonstrate in infants. Also See explanation-3 of session-6 of Skin of All India 2014-15 pattern of this book.