Updates

app.py

@@ -168,7 +168,8 @@ with st.form(key=f'question_form_{st.session_state.current_index}'):
         "Choose an answer:", 
         options=current_question['options'], 
         key=f"question_{st.session_state.current_index}_options",
-        index=None  # Ensure no option is pre-selected
+        index=current_question['options'].index(current_question['selected']) if current_question['answered'] else None, 
+        disabled=current_question['answered']  # Disable if the question has been answered
     )
     
     submit_button = st.form_submit_button(label=st.session_state.button_label)
@@ -207,7 +208,7 @@ if current_question.get('answered', False):
     # Change the button label immediately after showing the solution
     st.session_state.button_label = "Next Question"
 
-# This part handles switching to the next question on button click
+# Handle switching to the next question on button click
 if submit_button and st.session_state.button_label == "Next Question":
     new_question = generate_new_question(selected_module, modules[selected_module])
     st.session_state.questions.append(new_question)