BULLSHIT! I absolutely detest fake research:
A student of mine recently wrote:
“This is supported by a recent international survey of Oxford University, where it was demonstrated that In India those students who were persuaded to do their homework received a grade of approximately 85% in their public exam.”

This is obvious made-up bullshit because lots of students who do homework will not get such a high grade. It makes me angry because it is not even realistic and note that it’s not appropriate academic writing to state percentages without a full reference as to where this number comes which means stating the author, date, title, publisher…. and since you don’t have these in the IELTS exam and it’s completely inappropriate to do this. As an academic, this makes me bloody angry and since most examiners are academics it is likely to infuriate them also.

How to give appropriate examples?
Give illustrative examples based on your own experience. Note that the task instructions say: “include any relevant examples from your own knowledge or experience.” This is shown in the image a t the bottom of the page.

“For example, my nephew’s grades increased drastically after he started doing one hour of homework each night.” 

” For instance, when I was in my graduating year I spent almost all my free time on my homework and as a result, my grades increased dramatically”

“For instance, I have heard in the media that students who  spend most of their free time on homework  get much higher grades “

You can see more ideas from model essays I have written:
https://www.ieltsanswers.com/ielts-writing-essay-questions.html