Hello Aspirant,

Since you have not mentioned the name of examination for which you have doubt so it's quite difficult to guide you with an accurate information or solution but however the issue you are telling in the question will not create any problem because OMR sheet is scanned only for bubbles which you have circled/darken. So although it has some light marking or traces, then also it will not create any problem.

I hope this information helps you.

Good Luck!!