&lt;?php    function a&#40;&#41;      &#123;        function b&#40;&#41;        &#123;            echo 'I am b';        &#125;        echo 'I am a';    &#125;    b&#40;&#41;;    a&#40;&#41;;    ?&gt;
A. I am b
B. I am bI am a
C. Error.
D. I am a Error
Answer:A
&lt;?php    function a&#40;&#41;      &#123;        function b&#40;&#41;        &#123;            echo 'I am b';        &#125;        echo 'I am a';    &#125;    b&#40;&#41;;    a&#40;&#41;;    ?&gt;
A. I am b B. I am bI am a C. Error. D. I am a Error
Explanation: This will be the output- Fatal error: Call to undefined function b(). You cannot call a function which is inside a function without calling the outside function.