Ans: B. Alopecia areata(Ref Rooks 8/e p66.13, Fitzpatrick 6/e p732)Findings are highly suggestive of alopecia areata.The scalp appears normal in alopecia areata.In affected areas, anagen is abruptly terminated prematurely and affected hairs move prematurely into telogen, with resultant often precipitous hair shedding.The near pathognomonic 'exclamation point' hairs may be present, paicularly at the periphery of areas of hair loss.These sho broken hairs, whose distal ends are broader than the proximal ends, illustrate their inherent sequence of events: follicular damage in anagen and then a rapid transformation to telogen. White or graying hairs are, frequently spared and probably account, in cases offulminant alopecia areata, far the mysterious phenomenon of 'going gray overnight.'