#include &lt;iostream&gt;    #include &lt;vector&gt;    using namespace std;    int main &#40;&#41;    &#123;        vector&lt;bool&gt; mask;        mask.push_back&#40;true&#41;;        mask.flip&#40;&#41;;        cout &lt;&lt; boolalpha;        for &#40;unsigned i = 0; i &lt; mask.size&#40;&#41;; i++&#41;        cout &lt;&lt; mask.at&#40;i&#41;;        return 0;    &#125;
A. false
B. true
C. Both a & b
D. None of the mentioned
Answer:A
#include &lt;iostream&gt;    #include &lt;vector&gt;    using namespace std;    int main &#40;&#41;    &#123;        vector&lt;bool&gt; mask;        mask.push_back&#40;true&#41;;        mask.flip&#40;&#41;;        cout &lt;&lt; boolalpha;        for &#40;unsigned i = 0; i &lt; mask.size&#40;&#41;; i++&#41;        cout &lt;&lt; mask.at&#40;i&#41;;        return 0;    &#125;
A. false B. true C. Both a & b D. None of the mentioned
Explanation:In this program, We are fliping the vector values by using flip function.