#include &lt;iostream&gt;    #include &lt;queue&gt;    using namespace std;    int main &#40;&#41;    &#123;        priority_queue&lt;int&gt; mypq;        mypq.push&#40;10&#41;;        mypq.push&#40;20&#41;;        mypq.push&#40;15&#41;;        cout  &lt;&lt; mypq.top&#40;&#41; &lt;&lt; endl;        return 0;    &#125;
A. 15
B. 20
C. 10
D. Error
Answer:A
#include &lt;iostream&gt;    #include &lt;queue&gt;    using namespace std;    int main &#40;&#41;    &#123;        priority_queue&lt;int&gt; mypq;        mypq.push&#40;10&#41;;        mypq.push&#40;20&#41;;        mypq.push&#40;15&#41;;        cout  &lt;&lt; mypq.top&#40;&#41; &lt;&lt; endl;        return 0;    &#125;
A. 15 B. 20 C. 10 D. Error
Explanation:In this program, We used the queue template and the top method is used to retain the last but before element.