Which is the following is syntactically correct for vector<int> v?

• A. vector &lt;int&gt; :: const_iterator itr = v.rbegin();
• B. vector &lt;int&gt; :: reverse_iterator itr = v.begin();
• C. vector &lt;int&gt; :: iterator itr = v.begin();
• D. vector &lt;int&gt; :: iterator itr = v.cbegin();