Answer:
D: too much gaming can affect a students grades
Explanation:
"As long as students know when to stop playing"
The arugument given discusses time when it says "when to stop playing". This means that the argument talks more about how much time should be spent on gaming and nothing about the affects that gaming has on students. Because of this, we need to make sure the supporting sentence discusses time, which it does.
Option C also discusses time but the sentence reads "Teachers need to understand the downfall of over-gaming", the argument we were given talks about how the students need to know, not the teachers.
