The correct answer is: [B]: "to move" .
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Note: Even though we are taking about "birds" (specifically "Canadian geese") ; which do, in fact, "fly" , we must note the following text:
" As the New England weather gets colder, we enjoy watching...as they migrated south for the winter." .
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Base on the verb tenses used, and the specific language: "As the winter gets colder..." ; the implication is that "migrate" means: "to move" ; since the text implies that this is a seasonal, yet routine occurence—to a different LOCATION.
Furthermore, other animals migrate (that do not "FLY" — and that are NOT "birds".
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The correct answer is: Answer choice: [B]: "to move" .
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