Use the right role.
diff --git a/Doc/library/http.server.rst b/Doc/library/http.server.rst
index 4bf5178..1ca1620 100644
--- a/Doc/library/http.server.rst
+++ b/Doc/library/http.server.rst
@@ -301,7 +301,7 @@
print("serving at port", PORT)
httpd.serve_forever()
-:mod:`http.server` can also be invoked directly using the :cmdoption:`-m`
+:mod:`http.server` can also be invoked directly using the :option:`-m`
switch of the interpreter a with ``port number`` argument. Similar to
the previous example, this serves files relative to the current directory. ::