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

<%
  question.input_options.each do | option |
  option_id = "#{option.parameterize}_#{question.to_i}"
  radio_html = {class: 'radio', id: option_id}
%>
  <div class="form-group-multiples">
    <%= radio_button_tag('answer[radio]', option, (question.answer == option), radio_html) %>
    <%= label_tag(option_id, option) %>
  </div>
<% end %>

<% if flash[:error].try(:include?, question.to_i) %>
  <div class="error">Please select an answer.</div>
<% end %>