diff --git a/src/main/java/de/hda/fbi/db2/api/Lab01Data.java b/src/main/java/de/hda/fbi/db2/api/Lab01Data.java
index 01ab9005f967b7b0bb24c1750810f8c771448b88..3673c617dbcf825f3cdf07d1a5e323877b4941bf 100644
--- a/src/main/java/de/hda/fbi/db2/api/Lab01Data.java
+++ b/src/main/java/de/hda/fbi/db2/api/Lab01Data.java
@@ -16,14 +16,14 @@ public abstract class Lab01Data {
      *
      * @return questions
      */
-    public abstract List<Object> getQuestions();
+    public abstract List<?> getQuestions();
 
     /**
      * Return all categories.
      *
      * @return categories
      */
-    public abstract List<Object> getCategories();
+    public abstract List<?> getCategories();
 
     /**
      * Save the csv data in appropriate objects.