diff --git a/quiz/neuesquiz_app.py b/quiz/neuesquiz_app.py
index 783e819..ea517ae 100644
--- a/quiz/neuesquiz_app.py
+++ b/quiz/neuesquiz_app.py
@@ -4,7 +4,7 @@ from tkinter import font as tkfont
 
 DEBUG = True
 
-# Acces to Controller
+# Access to Controller
 from neuesquiz_controller import *
 
 
@@ -48,7 +48,7 @@ class Application(tk.Frame):
 
         # Radiobuttons
 
-        self.radios=list()
+        self.radios = list()
         selected_elements = self.controller.current_selection
         for count, (el_key, el_value) in enumerate(selected_elements.items()):
             r = tk.Radiobutton(self.lf_a, text=el_value,
@@ -106,7 +106,12 @@ class Application(tk.Frame):
 
     # TODO: coloring of correct answer in green
     def mark_correct_answer(self):
-        pass
+        # Was auf grün setzen? -> Element finden
+        for element in self.radios:
+            print("Element finden")
+            print(element.cget('value'))
+            # Ausführen: auf grün setzen. 
+            element['bg'] = "green"
 
     # TODO: coloring of selected answer in red if wrong
     def mark_answer_incorrect(self):
@@ -146,8 +151,13 @@ class Application(tk.Frame):
         
     def purge_radios(self):
         for r in self.radios:
+            r.grid_forget()
             r.destroy()
 
+        del(self.radios)
+        self.radios = list()
+            
+
     # TODO: reset of all elements
     def reset(self):
         pass