Answer
H
Work Step by Step
A vertical line means that the y does not change.
The only function where y is not included is $x=9$.
Also, recall that lines of the form $x=c$ where $c$ is a constant are vertical lines.
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.