Answer:
Homework is harmful and not the key to student success
Step-by-step explanation:
The above option is actually the best that serves the writer's claim.
This is true because looking at the passage, we see that after the student argued about the problem of homework and how it is not really beneficial to the students, the writer then went further to conclude that homework is harmful and not the key to a student's success.
So, the selected sentence is the correct answer.