Before revision:  Specifically, we ask which priorities are such that the strategyproofness of deferred acceptance (DA) can be recognized by agents unable to perform contingency reasoning, that is, when is DA obviously strategyproof Li17  ? We answer this question by completely characterizing those priorities which make DA obviously strategyproof (OSP).
After revision:  Specifically, we ask which priorities are such that the strategyproofness of deferred acceptance (DA) can be recognized by agents unable to perform contingency reasoning, that is, when is DA obviously strategyproof when is DA obviously strategyproof ? We answer this question by completely characterizing those priorities which make DA obviously strategyproof (OSP).