Answer: A

Reasoning: An unprovoked dog bite is treated as a high-risk (WHO category III) rabies exposure; post-exposure prophylaxis must be started immediately with a modern cell-culture rabies vaccine (and, if wounds are severe, rabies immunoglobulin). Waiting to “observe the dog,” killing the dog, or taking no action risks a uniformly fatal disease and is therefore unacceptable [Chhabra & Ichhpujani, 2003, PMID 12785276; Warrell, 2012, PMID 22342356].