Which corrects the incorrect pronoun or contraction in the sentence?
they're following the creek to it's source.
a.
its
b.
their
c.
there
d.
it is

It would be A.

The incorrect contraction in that sentence is it's. It's is a contraction for it is, so it basically means : They're following the creek to it is source. This doesn't make sense. So, you would replace it with the other form, which is its. Its shows possession.

Hope this helps!

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