Final answer:
The word that does not fit in the sentence is 'His.'
Step-by-step explanation:
In the sentence, 'The doors have been open all day,' the word that does not fit is 'His.' This is because 'His' is possessive and does not make sense in the given context. The other options 'It's,' 'Your,' and 'Its' can all be used as possessive pronouns to indicate ownership or possession.
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