The migrating geese fly south each autumn because ______ instinctively responding to changes in daylight and temperature.
Which choice completes the text so that it conforms to the conventions of Standard English?
- A
theyre
- B
their
- C
there
- Dcheck_circle
they're
Explanation
"They're" is the contraction of "they are" and matches the participial structure ("they are instinctively responding"). "Their" is possessive and "there" is locative.