#include&lt;stdio.h&gt;&nbsp;   int main&#40;&#41;   &#123;       int fd_socket;       fd_socket = socket&#40;AF_UNIX,SOCK_STREAM,0&#41;;       printf&#40;&quot;%d\n&quot;,fd_socket&#41;;       return 0;   &#125;
A. -1
B. 0
C. any integer value
D. none of the mentioned
Answer:A
#include&lt;stdio.h&gt;&nbsp;   int main&#40;&#41;   &#123;       int fd_socket;       fd_socket = socket&#40;AF_UNIX,SOCK_STREAM,0&#41;;       printf&#40;&quot;%d\n&quot;,fd_socket&#41;;       return 0;   &#125;
A. -1 B. 0 C. any integer value D. none of the mentioned
Explanation:To use socket(), the header files sys/types.h and sys/socket.h are required.