That option has existed since at least A97 (i.e. before the Office VBE was integrated into Access) and has always been on by default.
As mentioned in post #9, Require Variable Declaration was also on by default in A97
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The VBE was added in A2000 and its Options menu looked almost identical to that in current versions of Office
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However, as I also mentioned in post #9, from A2000 onwards, Require Variable Declaration became disabled by default in line with Excel & Word.
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