With this particular TG we're actually trying to accomplish two things.
First, we want to stay within the guidelines. Ensuring that our work is consistent with the guidelines means that students and instructors alike will have materials that easily fit into their lessons, lesson planning, and testing processes.
Second, we have to make sure the TGs do not introduced unusual conditions on students or instructors, when learning and teaching the concepts. As indicated in our previous response, because of the way sine waves are normally displayed (that is, horizontally) and the way the the question is asked, the student and instructor will expect to have values plotted above and below the horizontal X-axis rather than to the left and right of a vertically-oriented X-axis.
In this case, we recommend omitting every other label and/or stair-stepping the labels for the x-axis. This is consistent with the 4th bullet in GSTG 184.108.40.206