I am a beginner and created a multiple choice quiz using CheckBox.
The designs and blocks used are as follows:
Please help me, how can I save answer choices in Google Sheet? (Note: I have set the ID from Google Sheet)
If the checked checkbox is indicating the answer selected, then get the value for the answer selected and set this to your google form data.
Your checkbox logic is all wrong.
Use a ListView, List Picker, or Spinner instead.
Yes, right. Even though the checkbox is wrong it works as I expected.
However, as a result I had to arrange blocks that were not simple.
OK, thank you sir. I'll try using as you suggest
Sir, I have tried using listpicker, but I found a PROBLEM.
If each question item has the SAME listpicker content then the selected listpicker can be sent to Google Spreadsheet.
However, if the listpicker content is DIFFERENT, the listpicker that has been selected cannot be sent to Google Spreadsheet.
Please help me, Sir.. 
Google Spreadsheets do not store components.
They only store numbers and text.