skill-assessment-app/app/views/quiz/_radio.html.erb

<%  answer_string = answer.try(:answer) || answer %>
<%= form.collection_radio_buttons(:answer, question.input_options, :to_s, :to_s, {}, {class: 'radio'}) do | option | %>
    <%
      option_id = "#{question.question_id}#{sanitize_to_id(option.value)}"
      checked = answer_string == option.value ? 'checked' : ''
    %>

    <div class="form-group-multiples">
      <%= option.radio_button( id: option_id, checked: checked, data: { last: checked } ) %>
      <%= option.label(for: option_id) %>
    </div>

<% end %>

<%= render partial: "quiz/answer_errors", locals: {question: question, answer: answer} %>