In which line of poetry does the author use rhyme to connect words and emphasize their meanings?

Fiona fretted and paced, and feared for the future.
Nathan was man of his word, and a man who came through.
Tanya climbed each rung of the corporate ladder, while those around her grew anxious and madder.
Lin watched and he listened until his senses were sharp, like dogs at the airport trained for special security.

The line of poetry where the author uses rhyme to connect words and emphasize their meanings is:

Tanya climbed each rung of the corporate ladder, while those around her grew anxious and madder.