According to your requirements, you can change handleCheckboxQuestionInput to:

const handleCheckboxQuestionInput = (e) => {
    const answer = e.target.value;
    setSelectedAnswers((prevAnswers) => {
      if(prevAnswers.includes(answer)) {
        return prevAnswers.filter(e => e !== answer)
      } else {
        return [...prevAnswers, answer]
      }
    });
  };

and change at the input element to:

 handleCheckboxQuestionInput(e)}
 />

Hope it helps you