To support Sarah's claim that students should have less homework, the piece of evidence that best supports her argument is: "Students are staying up late completing homework and not getting enough sleep."
Explanation: This evidence highlights a direct consequence of excessive homeworkâstudents are losing sleep, which can negatively impact their overall health, well-being, and academic performance. Lack of sleep can lead to decreased focus, poor concentration, and reduced productivity, which reinforces the idea that too much homework is detrimental to students. In contrast, the other pieces of evidence focus more on student behavior, such as choosing to play video games instead of completing homework, or struggling with assignments because they are not grasping the material in class. While these points are relevant, they do not emphasize the broader negative impact on students' well-being as directly as the sleep-related evidence does.