Answer:
Han used a convenience nonrandom sampling approach
Explanation:
The convenience nonrandom sampling approach consists in collecting a sample just because it is convenient. This means that the subjects are easy to select.
Han did precisely this, he went to the teacher's lounge and surveyed the faculty present there. He did not put any further effort like, for example, wait for more teachers to have a larger sample or make sure the ratio between female and male teachers was the same.