title: How to disable a submit button after submission in PHP?
body: <p>I browsed through the other questions on this issue but couldn't find a satisfactory answer.
  I have a quiz website where the user selects an option from four options and then clicks submit. I want to disable the submit button after it has been clicked once. </p>
  
  <p>Is there any way to do this with PHP? If not, is there a way to do this with minimal JS.</p>