diff --git a/exam/ex.tex b/exam/ex.tex
index 34d87ec..b04ab27 100644
--- a/exam/ex.tex
+++ b/exam/ex.tex
@@ -92,7 +92,9 @@
     \item Poly1305 is also a message authentication code (MAC), which we
       discussed in the lecture.
 
-    \item \TODO
+    \item One advantage of EWCDM over Poly1305 is that the former is
+      nonce-misuse resistant up to the birthday bound while Poly1305 is not.
+
     \item \TODO
   \end{enumerate}