<p>Companies that wish to attend the Chicago Technology Fair must submit their applications <strong>by</strong> October 10.</p>
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<p>The correct answer is <strong>(B) by</strong>.</p>
<p>In this sentence, the word "by" is used to indicate the deadline or the latest time by which the applications must be submitted. "By" is commonly used in this context to specify a time limit.</p>
<p>(A) "in" is incorrect because it does not convey the idea of a deadline or a specific time limit.</p>
<p>(C) "to" is incorrect because it does not indicate a deadline or a specific time limit. It suggests a direction or destination instead.</p>
<p>(D) "until" is incorrect because it suggests that the deadline extends beyond October 10, which contradicts the requirement of submitting the applications by that date.</p>
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