Fix markup errors.
diff --git a/Doc/library/unittest.rst b/Doc/library/unittest.rst
index 63ad705..75070f7 100644
--- a/Doc/library/unittest.rst
+++ b/Doc/library/unittest.rst
@@ -1879,7 +1879,7 @@
:ref:`deprecated unittest methods <deprecated-aliases>` are also
special-cased and, when the warning filters are ``'default'`` or ``'always'``,
they will appear only once per-module, in order to avoid too many warning
- messages. This behavior can be overridden using the :option`-Wd` or
+ messages. This behavior can be overridden using the :option:`-Wd` or
:option:`-Wa` options and leaving *warnings* to ``None``.
.. method:: _makeResult()