fix duplicated question title for question 67

jbkly · jbkly · commit 658976d93ced · 2019-07-08T23:29:01.000Z
diff --git a/README.md b/README.md
@@ -2086,7 +2086,7 @@ The `Labrador` class receives two arguments, `name` since it extends `Dog`, and
 
 ---
 
-###### 67. With which constructor can we successfully extend the `Dog` class?
+###### 67. What's the output?
 
 ```javascript
 // index.js
