To show that \( \overline{NO} \) is a constructed copy of \( \overline{PQ} \), Thuy needs to verify that the lengths of the segments are the same. The process involves measuring the distance of one segment, and then checking if the corresponding segment is the same length.
The correct response would be:
She must measure the distance from point M to point Q using a compass and place the compass on point M to see if point O is the same distance.
This response correctly indicates that she is measuring \( \overline{MQ} \) with a compass and checking if \( \overline{MO} \) is equal in length.