#include&lt;stdio.h&gt;   #include&lt;stdlib.h&gt;&nbsp;   int main&#40;&#41;   &#123;       int *ptr;       *ptr = 10;       *ptr = 20;       printf&#40;&quot;%d\n&quot;,*ptr&#41;;       return 0;   &#125;
A. 10
B. 20
C. segmentation fault
D. none of the mentioned
Answer:A
#include&lt;stdio.h&gt;   #include&lt;stdlib.h&gt;&nbsp;   int main&#40;&#41;   &#123;       int *ptr;       *ptr = 10;       *ptr = 20;       printf&#40;&quot;%d\n&quot;,*ptr&#41;;       return 0;   &#125;
A. 10 B. 20 C. segmentation fault D. none of the mentioned
Explanation:The segmentation fault occurs because memory for the pointer has not been allocated in this program.