#include &lt;stdio.h&gt;    #define foo(m, n) m ## n    int main&#40;&#41;    &#123;        printf&#40;&quot;%s\n&quot;, foo&#40;k, l&#41;&#41;;    &#125;
A. k l
B. kl
C. Compile time error
D. Undefined behaviour
Answer:A
#include &lt;stdio.h&gt;    #define foo(m, n) m ## n    int main&#40;&#41;    &#123;        printf&#40;&quot;%s\n&quot;, foo&#40;k, l&#41;&#41;;    &#125;
A. k l B. kl C. Compile time error D. Undefined behaviour